So a question came up in an Oly class recently: Are Oly shoes just a crutch? Shouldn't a person - especially a CrossFitter - just focus on bare bones functionality? ... After all, CrossFit is about GPP (general physical preparedness)?
First let us look at the concept of GPP and functionality. CrossFit is all about functional fitness. Functional fitness means it is adding to your daily life. Now, just like your friends tease you about your Paleoness - you can take the functional/real debate to an extreme. No, you will never have your oly shoes on when you need to "clean" and object off the floor in real life.. but you probably won't chalk up either... If the point was to mimic real life, we would be using babies, grocery bags and luggage instead of barbells. But barbells are a great simplification for the journey to strong.
Secondly, for those of you who have put time and energy into your mobility, oly shoes are not a crutch. Oly shoes - mobile or not, put you into a more advantageous and stable position. But the shoes are not doing the work for you, and as your squats and oly lifts go up, your total strength is going up. When you take the shoes off for other movements or even lighter squats/oly lifts (e.g. WODs), yes, you may not lift as much as you do with your shoes, but you are still stronger shoe-less because of the gains you made with them.
My short answer on the matter: it depends on why you are using them. If you are using them to compensate for a lack of mobility, then yes - they're a crutch. If instead of spending the 3-10min a day on your poor positions you just throw on a pair of shoes, then they are keeping you from hitting a squat position that you should be working towards on your own. But, if you have seen a lot of top Olympic lifters, they are very capable movers with great mobility... yet, they've still got their oly shoes on.
At the end of the day, it's your training, so it's your call. Some wear them purely for strength, with it being an end in and of itself. Others wear simply to learn the lifts. Others to prepare themselves for different styles of training... etc. So long as you are looking to maximize your capacity, and not to avoid a deficiency, oly shoes are fair game.