Eh, I'm pretty lenient with "cheating."
Obviously, I don't think it's right to go around ripping through everything with a Pokemon with 999 everything, but I've created Pokemon with the nature, EVs, and IV's I want. I don't have the time and patience for that, unfortunately, and while I do feel bad about those who do take the time, that's just how it is. If it makes anyone feel better, I level them up and get all their moves myself (like if I once sat down and played through Voltorb Flip for a while to save up for an Ice Beam TM).
I also see no problem with things like obtaining old event Pokemon or reobtaining a TM because really, if TM's are going to be one use items, there should be at least one way to be able to get it again after using it, whether it's Battle Frontier or Game Corner or just buying.