Friendship

]What does it mean, when someone from a super wealthy family likes being frinds with you? As someone coming from an normal/working class family i find this extremely strange. There is this girl that i met recently, we get on extremely we're quite atm, and she seems like a lovely person genuinely. But she was adopted by a very wealthy couple from what she's told me so far, not that it is a problem, she's aware as well that i'm not super wealthy but from a normal working class background. She's not the type boast or anything. But sometimes i question our frienship, like is it safe for me to be friends with her ? I dont know what rich people are like. We haven't had any issues so far, but something about our friendship scares me, I don't know how to exaplain it, Is it normal to feel this way or am i crazy?.