Now that I think about it, I'm really glad that fighting games aren't as popular as something like Halo. People who know absolutely nothing about competition are much less common in the fighting game community.
There is no absolute rule on what is and isn't cheating. It's circumstantial. If you agree to a set of rules and break those rules, then you are cheating. If you do something that another player considers to be unfair, you're not necessarily cheating. What the developers intend, and what is or isn't a glitch is completely 100% irrelevant in a discussion of cheating. Cheating is breaking the rules, and if there are no explicit and agreed upon rules, there cannot be cheating. Cheating does not exist in casual play.
You can cry "cheap" and "cheater" until you're red in the face, but it's not going to make the experience any more enjoyable, and you're just as bad as the little kids who call eachother f*****g n*****s on Live.