Shareholders invest in publicly traded companies for many reasons, not least of which is to make decent returns. Generally speaking, investors hope their companies invest capital into productive channels: inventing, innovating, delighting customers with their products, and otherwise paving the road to growth, leading to fantastic financial results over the long haul.

Unfortunately, there is a big sucking sound emanating from many corporations large and small, and it deserves scrutiny from American investors and citizens alike.

Did any of us really invest in public companies hoping for them to waste billions in Washington?

Voting for transparency
Corporate political spending has increasingly reached the limelight ever since the Supreme Court's Citizens United ruling. In the last several years, shareholder proposals demanding transparency in or even banishment of political spending have increased in frequency, and a significant number of shareholders have supported such proposals.

According to Proxy Monitor's scorecard, which tracks votes on shareholder proposals at the top 200 American public companies, shareholder resolutions related to corporate political spending at some major companies received significant numbers of votes in 2012.

For example, 38.56% of AT&T's shareholders voted for a shareholder proposal from Domini Social Investments asking for a report disclosing political spending.

The American Federation of State, County and Municipal Employees, or AFSCME, garnered some major support in favor of lobbying disclosure, with 28.51% approval from shareholders at Verizon and 32.35% approval at Abbott Laboratories.

In a major victory, Trillium Asset Management's simple request for a political spending report rounded up a whopping 41.08% of shareholder votes at CenturyLink.

Who did your companies "vote" for?
Fast-forward to the present, and the proxy pre-season is already under way. This week, a group of investors announced that they have filed shareholder proposals at a variety of major, well-known American public companies, demanding an end to corporate political contributions.

The coalition consists of Clean Yield Asset Management, Green Century Capital Management, Zevin Asset Management, Responsible Wealth, and Harrington Investments.

Reacting to what they call last year's "unprecedented level of outside spending" in American elections, the investors are filing proposals hoping to ban political spending altogether at the companies they're targeting.

ExxonMobil (XOM -0.48%) is one such company; Zevin Asset Management is asking its board to look into the feasibility of adopting a no-spending policy when it comes to political spending. (Last year, 23.60% of ExxonMobil shareholders voted for a report on political spending filed by Laborers National Pension Fund.)

Target (TGT 0.01%) has also been targeted by individuals associated with the organization Responsible Wealth, also asking for similar research into the concept of banning the practice. A proposal last year by Green Century Capital Management to prohibit all political spending at Target received a mere 4.60% in shareholder support.

Interestingly, Harrington Investments is proposing that Starbucks (SBUX 0.10%) end political spending from treasury funds and pledge not to form a political action committee, commonly known as a PAC. In late 2011, Starbucks CEO and founder Howard Schultz proposed that corporate America cut off political donations to coerce Washington into getting its act together on economic issues.

Obviously, the aforementioned investors want corporate America to cut off its political spending altogether as opposed to using it to influence Washington either way.

Money really talks through this "free speech" ruling
One thing that's often left out of the debate is how much unions contribute to political campaigns; what unions can do also expanded through the Citizens United ruling.

Many critics also see a threat of unions' influence on public companies and the political process as it pertains to economics and corporate actions. Last year, I talked to Proxy Monitor's James Copland about what he called "alarming trends" including political spending proposals, which he believed were more about philosophies and agendas than shareholder value in the traditional sense.

As it turns out, in 2012 shareholder votes in favor of political spending disclosure and other related proposals received 17% of the overall votes at the companies that Proxy Monitor tracks, down from 22% the year before. However, it's worthwhile to note that the number of proposals on the topic increased by 20% over the year before.

Investors: Wake up to waste
Investors of all stripes should ponder how they feel about their companies' political spending. The coalition of investors seeking to end such spending pointed out that last year, Chevron's (CVX -0.13%) $2.5 million directed into a Super PAC was the largest corporate donation into a Super PAC ever. Whether the companies whose stock you own are supporting your political cause, candidates, or economic beliefs is in question -- and it shouldn't even be an issue in these highly contentious times.

Meanwhile, what good this type of spending actually does for any individual company's financial health is extremely questionable. The coalition pointed to a 2012 study conducted by the University of Michigan that looked at the performance of companies that shelled out money for political ends over the 1991 through 2004 time frame. These companies exhibited slower growth, fewer investments in and spending on research and development, and poor corporate governance policies.

It's not rocket science: Corporate money spent on politics could be used in far more productive ways, like ensuring public companies thrive in an operational environment, not a regulatory one, and make our economy more competitive and generate more productive employment. Right now, millions of dollars are being squandered oiling the Washington political machine. As shareholders, we should fight for transparency on political contributions by our public companies -- or even eradication.

Big Business (and, don't forget, Big Unions) seeks to influence elections and government policy-making through its almighty bucks. It's time investors and citizens stop looking the other way and put an end to it. There are far more productive ways to spend money.

Check back at Fool.com for more of Alyce Lomax's columns on environmental, social, and governance issues.