I can't speak to smash fans specifically, but I know back in the day there was that general sentiment toward the people who wanted to only do instagib and various pro-mods for Unreal Tournament. The general idea was that by not engaging with the vast majority of the content they weren't "real" fans and they were less likely to buy any expansion packs or sequels.
Obviously we were totally right back then and the smash crowd is wrong and childish. But I suspect the principle is still the same. By choosing to disable "most of the game" they aren't "really" playing the game and are instead playing the variant of it that they prefer.
