Moving past all the usual material stuff, one thing that sucked for me growing up was that I couldn't just up and go places when invited, even if it was free or their parents covered the cost of the activity. My mother was always broke and though we had a car, gas was reserved for the work commute only. I couldn't just "get a ride" from my mom and she never had spare change for the bus. Every dollar was accounted for.
I got a lot of "come to the movies with us, and don't worry I'll pay for you just be across the city by 5:30".
It sucked having to explain yet again that no money meant no money for anything, even a ride.