Oh, it's not just that. Someone made a blueberry dress up game on there some years ago. So long as it's weight gain, inflation, even growth, it can go up there. It's basically anything to do with getting big. You can even find a visual novel that has only one character who gains weight, called "Growth Academy", on there. Or there's "Blueberry Bushwhacking", another visual novel but more about adventure.
It's not only games, either. There are plenty of topics on mods, art, even writing help - some are a few glossaries for describing growing body parts, clothing damage, even things to do with a belly.
Edit: recently found out we have tags for bimbofication too!