But don't tell Grandma

Your grandparents probably wanted someone to watch the house and also to give you some cash. They probably just didn't want you to feel bad about taking so much.

My mother is like this. Me and my sister are opposites. My sister wants everything and more while my mother practically begs me to get something. She knows I don't like getting things, but she found out my favorite animal is the Fox and Owl for the ground and sky respectively. So she does her best to buy anything that is a fox or owl. I have an entire shelf filled with necklaces, plushies, rock, dogtoy, and/or porcelain items all with either a fox or owl on it. She also bought me a plush doge thinking it was a fox XD.