Not sure I understand your question. By "paying for quick service, regular or deluxe dining", do you mean paying for the QS Dining Plan, the Regular Dining Plan, or the Deluxe Dining Plan such that these would then be compared to getting a
free dining plan? Or do you mean paying out of pocket for quick service meals, for basic TS meals or for Signature meals, and then comparing that against free dining?
i did indeed mean the former-paying for meal plan-or receiving free dining, which as you correctly say, is obviously not actually "free".
If you mean the former, it should make no difference whatsoever. Once you are in the Dining Plan system, your meal is pre-paid, so you order what you order. I suppose that one could rationalize ordering a more expensive entree if you "paid" for the dining plan, and perhaps ordered just a light meal if the DP was free. But remember that the dining plan is never free. Even if they call it Free Dining, you have paid more for your vacation in other ways, specifically, the room rate. So in reality, one should never conclude: "What the heck. I got free dining, so I'll just have the pasta instead of the steak." Instead, that person should be saying: "I just paid $180 for my room instead of $130, so I am going to make up for it by ordering steak."
If you mean the latter, then, yes, being on a DP always influences what you order versus paying out of pocket. When you pay out of pocket, salads and appetizers start to look very, shall we say, appetizing, and $34 entress start to look a lot less appealing. And when you are on a DP and salads and appetizers are not included, then that section of the menu looks less appealing, as those would add on to your bill and upset whatever savings you thought you were achieving.