Did strict primal, then less strict, then a bit less... you see where I'm going. I have Celiac's disease, so that stopped me from going down that path too far. Do I indulge on occasion? Yes. Homemade ice cream (my own), dark, sea salt chocolate, the occasional GF dessert from a really great restaurant.
What bothers me moreso than "cheating" as a term, is the value we've placed on food as a social connection. It's intent, first and foremost, is to nourish the body. Now, let me not kid you, I am a damn fine cook, and I make really yummy meals. But if I go to a friend's house and they are serving up nachos, chips, and other unhealthy bits, I'm steering clear. Why does it matter if I don't eat it, or I bring my own food? I'm not saying it is wrong to indulge -- don't misunderstand me. But it saddens me that choosing to eat better food and not eat crap has become the equal to feeling like a social miscreant.
Perhaps this topic is simply one that is bothering me more today, but that is what I think of when I read this question.