So, if, for example, we go to the restaurant together, you will need to pick up the check for the both of us.
That's another pretty standard thing. We all assume that every expense will be taken care of, from coat-check to tip. We even assume that if you ask us if we need something, it's because you want to offer us a gift.
Let's say you did ask me if I needed something and then we pass in front of a sunglass shop and I say that I would need a pair and we proceed into the shop, it's assumed that you would be paying for the glasses unless you raised an objection during the purchasing process.