At The Motley Fool, we love stocks. We love talking about stocks, and we love buying stocks. Our writers often buy shares of the companies we're talking about. It's kind of baked into our Fool DNA.

Image you're reading an article called "This Stock Is Going to the Moon!" And then you get to the end of the article, and the author doesn't own the stock. You might think, "OK, he's a dispassionate observer, a neutral person, and he has no bias." All that might be true, but he also has no skin in the game.

Personally, if I really think a stock is going to the moon, I buy shares. So here are two stocks that I bought this week.

People sit around a table having a conversation as one of them uses a laptop with financial information on the screen.

Image Source: Getty Images.

1. On Monday (Aug. 30), I bought shares of The Joint Corp.

The way I discovered this one, I was participating in an audio show The Motley Fool does on Clubhouse (an app you can download to your phone). We do a Tuesday show and a Thursday show, two hours each day at 11 a.m. If you want to chat with us, that's a great way to do it.

Anyway, a week or two ago, another Foolish contributor named Neil Patel pitched a small cap, The Joint Corp. (JYNT -5.08%). He hasn't bought it yet because it's too expensive. I was like, "Ooh, I love stocks that are too expensive!" The Joint Corp. is a small-cap, and five years ago it was a micro-cap, so the stock chart is pretty insane. It's up 3,700% in five years.

JYNT Total Return Level Chart

JYNT Total Return Level data by YCharts

I'm excited about this one because it's a classic rule-breaker. The Joint Corp. offers chiropractic care in a friendly environment that's completely different from a doctor's office. You walk in (they don't take appointments) and pay cash (you don't need health insurance). The doctor helps you with your back. You pay about $30. You're out quick.

That seems simple enough, like getting a haircut or a massage. What's revolutionary is that this is healthcare. You're seeing a licensed doctor and he's helping you with your back pain and your bill is $30 and you don't need insurance.  

Peter Holt has been the CEO since 2016. As far as I can tell, Holt has no healthcare experience. He's a complete outsider to this industry. All his background is in retail, working at Mail Boxes Etc. and UPS, then running a yogurt business that acquired Planet Smoothie. What do mailboxes or yogurt have to do with chiropractic care? Nothing! So it might seem like Holt would be a bad fit as CEO.

Actually, though, his outsider status and franchising background is probably why the stock is rocking so hard. In Q2 2020, The Joint Corp. sold 11 franchise licenses. In Q2 2021, it sold 63 of them. Chiropractors are jumping in because the initial build-out cost for a franchise is only $180,000, while the average Joint Corp. clinic pulled in $489,000 in sales last year. And most of that money is going right to the chiropractor, who doesn't need expensive equipment or a lot of support staff.

The stock may look pricey at 21 times sales, and indeed, that's very expensive for low-margin retailers. But it's not bad at all for high-margin healthcare! The profit margin here is 24%, with revenue growth of 60% in the most recent quarter. You convinced me, Neil, I'm in.

2. On Thursday (Sept. 2), I bought more shares of Pieris Pharmaceuticals

In late 2019, I bought shares of a tiny biotech, Novavax (NVAX -2.61%), when it was $6.76 a share. The only thing that kept it from being one of those awful penny stocks was a 1-for-20 reverse split earlier in the year. It was a micro-cap and it was hated, but I was bullish. In January 2020, the stock was still ugly, dropping to $4 on no news. I actually bought some more. (I had to ignore that voice in my head that said "this is really stupid.") I limited my risk by keeping my position tiny, so if it went to zero it wouldn't hurt too badly.

Now Novavax is trading hands at $270, and I'm up almost 5,000% in under two years. So I'm happy, and I hope some of my readers are happy, too. Can I do it again? Maybe not. But it's fun to try!

My pick for a moon shot in 2022 is Pieris Pharmaceuticals (PIRS -1.54%). I opened up a tiny position in June, buying 200 shares at $3.50. If that seems kind of tentative, yes, yes it is. That's because Pieris has no profits, barely has revenue, and has no drugs on the market. As a matter of fact, we don't even have phase 2 data on any of its offerings yet. Pieris is a highly risky biotech.

My family portfolio is filled with highly risky biotechs,  and every year it seems like my worst performers are highly risky biotechs. But that's OK, because my positions are small, and a few winners can make a big difference. I have a few larger positions that are high-confidence -- mainly profitable biotechs, or companies on the verge of FDA approval.  And then there's Pieris. I bought more shares in July, and more shares in August. And this week I added some more. But it's still a very small investment. My No. 1 stock, Shopify (SHOP 0.31%), is 67 times larger than my Pieris position. 

Nonetheless, I want to own Pieris because if the phase 2 trials are positive, the upside is far bigger than usual for a drug company. Pieris created and owns the rights to Anticalin drugs. These drugs are eight times smaller than monoclonal antibodies, a major class of pharmaceuticals. Why does that matter? Well, for instance, antibodies can't go into the lung. The molecules are too big.

If you're fighting asthma, a drug that can access the lung is very helpful. Certainly AstraZeneca (AZN -0.70%) thought so. Back in 2017, the Big Pharma company paid $45 million to acquire rights to Pieris' asthma drugs. The companies expect the phase 2 data read-out next year. 

Success would be nice, and there are significant dollars waiting for Pieris just based on its existing drug collaborations with various companies, including Roche (RHHBY 0.10%) and Seagen (SGEN). All these drugs are several years away from a possible FDA approval. Nonetheless, the upside is exciting. If the drugs hit all their milestones, these collaborative deals are worth almost $9 billion to Pieris (not including royalties). That's massive for a company with a $350 million market cap. And this $9 billion is actually just the tip of the iceberg. Success with one molecule increases the value of the whole darn library.

How big is the library? Pieris owns the rights to 100 billion Anticalin molecules. That's why I'm adding to my small position now. The upside is too big to ignore.