I fit in the sometimes category.
I send it back only in two cases:
1) I recieve something I did not order... like fries instead of a baked potato.
2) If something is really cold I ask if they could kindly pop it in thier microwave because 'I took too long to eat it' and prefer it hotter.
They usually end up redoing it because they understand that it was thier mistake... not mine.