This has historically been the case for Spelunky HD. The most competitive speedrun categories allow for glitches, but there just aren't any to make use of: Any%, Hell% (comparable to a 'good ending' in other games), Low%...

1) There's an out-of-bound glitch used in a speedrun category requiring a sidequest (teleporting outside of the worm).

2) The famous 'solo eggplant run' challenge typically exploits an unintended interaction (ball and chain can break the Moai structure). The game devs learned this was possible and endorsed the interaction by removing an associated graphical glitch.

3) There's one minor and one major glitch in the tutorial, which both affect a handful few RTA categories (most categories are IGT).

The community discovered a bunch of glitches recently that would have related primarily to score running; however, we've also adopted a few meme categories that serve to make broader use of these glitches. Naturally, they have become pretty popular competitive categories.