How To Bring Up Money With My Boyfriend?

My boyfriend (we’re both seniors in high school) has a really good job on his family farm that he gets paid for. His parents cover his car payments and all other necessary costs for working for them. He always talks about working, and how he makes $600 in one weekend working extra, etc. etc. However, when it comes to date night, he always tells me he’s short on money until he gets paid again so we should probably just go to his house and “watch movies” unless I can pay for myself because he’d feel “really bad” making me do that. Now we haven’t been dating for that long, maybe a few months, and I don’t mind hanging out but I’d like to go on a date every now and then. He hasn’t paid for me since homecoming, which was in October. I can’t find a way to bring this conversation up without offending him. If money really was an issue I wouldn’t, but he always claims to have it and I feel like he’s using money as an excuse to just get me over to his house just to hook up. How can I discuss this with him without seeming rude?