I've always taken this view, although I don't play multiplayer so I'm exclusively talking single player games here. I mean, hey, if you figure out a way programmed into the game that solves a problem, then using that is just plain logical. I consider it smart and reasonable. I mean, put it this way, if it weren't a game, and it were a movie, and the characters have available to them a way of doing something tactically smart that would ensure victory, and they don't take it, I would think those characters are pretty darn stupid. If I recognise a weakness or an opening, I'm going to take it. I haven't given myself any advantage over anyone else who has ever played the same game, or altered anything in the game to my benefit.
I mean, if you consciously choose not to use something available to you for the sake of challenge, that's fine too, but calling people who play in a different way from you "cheaters" is more than a little petty. I mean, that's like claiming it's "cheating" to use a Master Ball to catch a Pokemon or something.