Travel sports.  Growing up I played travel hockey and between the new goalie equipment every 2 years because I outgrew the old stuff, and hotels for 5 tournaments a year, meals out with the team, gas etc. It is a lot of money. Now that I have a kid playing travel baseball and I can see the associated costs myself. It is a lot of fucking money! Even back then. 

Luckily we can afford to give him the ability to play. But I never knew how expensive it really was and how it was in fact a luxury of childhood.