We have the same cart rules, about half the time dd (3 today!) ends up in the cart, but giving her some leaway at the start helps her see it as fair...well somewhat fair. One real battle area has been dressing, but I've de-tagged all the clothes, offer a few choices and give more time so she gets to do it all herself. I remember ds as more tantrum prone, but probably I have learned a lot from his two's!