I suppose I see this a couple of ways -
For one, a gym is a business whose client base is local. If the gym can say "Come join us! We had 3 (or 4 or whatever) teams compete at The World Championships of Cheerleading this season!" Many parents would say kWhoa, that's awesome...I want Susie to go to Disney, too!" The gym gets new athletes. Doesn't really matter if those teams placed at the bottom on preliminary day - they still went to Worlds, and a gym can use that as a marketing tool to pull in local clients.
Two, the gym isn't making money off of performing well at Worlds, for the most part. If crossovers are used to get a bid, they can't be used at Worlds, and in all liklihood won't perform as well at Worlds. That's a disappointment, to the athletes on that team, if nothing else. Plus, it sucks for that team that could have had the bid, had the team not used the crossovers.
So, at the end of the day, a gym does what it does for business, not necessarily for the love and appreciation of the cheer world.