Maybe it's not cheating per se, but maybe it's to denote a different class of players. Those who snake (I'm assuming it's the same in Mario Kart DS as in F-Zero GX) exploit some glitch or hard-to-do thing in the game to leave everyone else in their dust. Players who can't snake can't hope to catch up. Players who do snake are in the same league and become challengers for snakers. But if anyone calls a Mario Kart DS player an amateur because they can't snake, go ahead and punch their lights out. They're just different classes of players.
I'm saying this in a vain attempt to justify getting totally whooped by some veteran players at Smash Bros. Melee, who were shinesparking and move-canceling and top+A-on-the-ground'ing all over the place. They looked like they were floating. Yes they're experts, but they're also on a whole other plane that I don't think I'd ever reach unless I learned those moves. Does that make me a beginner? I don't think so.
By the way, recently got Smash Bros. Brawl. Woo! I think Sakurai said that people who play Brawl expecting Melee moves and speed and all that are going to have a hard time adjusting. And... yeah. I mean, it's going to take me a while to get used to it, Brawl definitely feels different from Melee. And everything does seem slower, or at least characters have been given wider ranges in speed. Because of this, I'm back to liking Fox again since he can move.
But one of these days, I'm going to have to put Bunny Ears on Sonic and watch him outrace the racers at Big Blue for myself.