I never plan any cheats. They happen incidentally more than often enough. For example, you go to someone else's house and you don't get a choice of what to eat. Or someone buys you food (without you asking for it) and you don't want to hurt his or her feelings by rejecting it.
I cheat a couple times per week, but never on purpose, pretty much only when I don't have any other choice.
It also depends what you consider "cheating." Right now (pre-tournament), I consider eating pretty much anything that isn't whole food cheating.