He told me don’t tell his mom he buys me stuff.. EDIT

Okay so my boyfriend and I just moved in together, he was living with his mom at first. So he took me shopping yesterday then on the way home he tells me “don’t tell my mom I spend money on you” like wtf! Although I wasn’t anyway because it’s none of her business but I found it quite odd he would say that. I’m just trying to figure out why he would say that, what do you ladies think?

His mom doesn’t support him at all! He works and make his own money! And I did ask but he said to not worry about it just don’t tell her !!! I asked for opinions as to what you guys think about this, some of y’all are no help!