Anyone telling you that Halloween falls on a single autumn evening might be wrong on both counts. Disney (NYSE:DIS) is kicking off its Mickey's Not-So-Scary Halloween Party at Disney World's Magic Kingdom tonight, a couple of nights earlier than it did last year.

Yes, it's mid-August. It's also scorching hot in Florida this time of year, unless guests are being cooled off by a drenching tropical thunderstorm. However, Disney and rival Comcast (NASDAQ:CMCSA) have come to realize that Halloween is big business for theme park operators, and with peak summer travel season now fading in the rearview mirror, it's never too early to start cashing in on the late-October holiday.

Fireworks behind the Main Street railroad station with a pair of Halloween jack-o-lanterns in front.

Image source: Disney.

Some tricks get you treats

Rolling out its signature Halloween event a whopping two-and-a-half months before the actual holiday may seem outrageous, but it's a gold mine for Disney. It closes the Magic Kingdom early for day guests, only to charge a new wave of costumed turnstile clickers between $79 and $135 to experience the generous candy stations, unique meet-and-greet experiences, and seasonally spiked rides and performances that start at 7 p.m. tonight. 

Comcast's Universal Orlando won't get rolling with its Halloween Horror Nights until early next Sept. 6, but even Disney's biggest rival is getting an earlier-than-usual jump on the season. It also closes Universal Studios Florida early, replacing those day guests with folks who pay $68 to $94 each to enjoy the creepy scare zones and 10 industry-defining walkthrough mazes. Lines can get pretty long for the houses, opening the door for Universal Orlando to sell access to expedited queues for the attractions. 

Historically early starts for both events is welcome news to Disney and Comcast investors. Mickey's  Not-So-Scary Halloween Party and Halloween Horror Nights don't happen every night, but the summertime launches frees up Disney and Comcast to squeeze more of the premium-priced nightly events into their operating calendars. There will be a record 36 Mickey's Not-So-Scary Halloween Party nights this year, two more than last year. Comcast is adding even more nights with an entire extra week this time around. 

The incremental revenue comes at a great time. Disney stunned investors earlier this month by posting a decline in attendance at its domestic theme parks in its latest quarter. Comcast's report for the same three months featured an increase in attendance across its theme parks, but the segment's 4% year-over-year increase in revenue was actually worse than Disney's top-line growth.

The trend should improve for both companies in the current quarter, particularly Disney, which will open Star Wars: Galaxy's Edge in Disney World later this month. It will also be the ambitious expansion's first full quarter of operations at its original Disneyland park in California, as the new land was available for all guests without reservations for just one week during the prior fiscal quarter.

Halloween is here, and for investors, that will mean more treats than tricks with Disney and Comcast putting more weight behind their premium seasonal offerings. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.