I don't really see this as diet with "cheat" days or meals, but rather a lifestyle change. That said, what I noticed when I would have something like bread or a sugary food, it made me feel so bad (stomach ache, nausea, GI issues, etc.) that I found I didn't want those foods anymore. While they may have tasted great at the time, the side-effects didn't make it worth it in the long run. That's not to say I haven't had grains or other things not really part of the "plan," and never will again but boy do I feel it afterward.

But to answer your question, no, I don't think one "cheat" meal or day would completely derail you, unless you are one of those folks that are truly addicted to sugars and just one bite is a slippery slope. It's more likely you'll find that as time passes, your taste buds will change and those types of food will no longer hold sway as they'll just taste excessively sweet and artificial.

Personally I haven't had a difficult time giving up the non-primal foods, and when I have had them ... like last sunday, when I was on a trip....the side effects sucked. I had food cravings even though I just ate, broke out with acne, skin wasnt soft (I kind of liked that change and missed it).
Lots of people follow the 80/20 rule, where you eat primal/paleo 80% of the time. Some days I gravitate towards that because I still eat bakery muffins a couple times a week. And there's nothing wrong with that...but in general, it's not worth the side effects once you get used to eating primal/paleo .
As for chipotle, what about a burrito bowl sans beans and rice? Can still have full fat, veggies and meat, and will still be delicous.

It's not silly at all. I remember when I first considered eating paleo, I kept thinking about how I'd never get to eat bagels or pizza again. Or oatmeal. After a while as your body gets used to being fueled with foods that are satisfying and nourishing, you really will find that you won't miss the other foods. But I say give yourself at least a month of truly eating paleo before trying regularly scheduled cheat" meals. If you start at 80/20, you never will fully see the effects of eating paleo or primal. I recommend trying a Whole 30 challenge (read It Starts With Food).

As time passes and you see the incredible transformation in your mood, body composition, sleep, skin, and appetite, and you learn how to cook the most delicious meals from whole foods, you might find yourself not missing Chipotle as much. Or maybe you still will, and in that case, you go out and get yourself that burrito and you have the time of your life! And guess what? That burrito becomes not a "Cheat" (I don't like the negative connotation) but a wonderful special treat that you only get to have once in a while. I know that I didn't eat even 80/20 primal during the holidays, but that's because I enjoy my family's traditional cooking because it's special to me.

You'll figure out what works for you, that's what it's all about. No one size fits all. Welcome to the paleo/primal lifestyle!

I'm primal, not paleo, but I go to Chipotle about once a week and get a burrito bowl with double meat (1 serving of steak and another of chicken), fajita veggies, salsa, cheese and guacamole with lettuce and cilantro on top.

I've found that carbs usually work only as a vehicle for the yummies: fat and other stuff you can put on it. It's not like pasta and bread have much flavour: it's what you add to it that makes it so good to the tongue.

Example: I don't like toasted bread alone, but if I think of it with lots and lots of butter............omg, I'm still craving it!

I never "plan" a cheat day or meal, that way I don't feel like I should eat it if I don't want it.