Boats are overpriced, and continue to cost you more during the entire time you own them - I should know, I've owned more boats than keyboards. In additional to slip fees, winter storage and maintenance, if you really want to go big time, you can join a yacht club and really blow some hard cash.

Fishing tackle is overpriced - got lots of that too. I just gave my son a 12-weight saltwater fly rod and reel that cost nearly as much as a Genos. I'm too old to do that stuff anymore. Carol says I'm too old to do a lot of stuff anymore.;)
Golf is a VERY expensive hobby, keyboards are chump change in comparison to country club memberships and greens fees in this part of the world. Last time I checked, a decent golf cart went for about $3,500 plus batteries.
Now, how about ridiculously overprices - cars, mini-vans, pickup trucks, SUVs - Even used they tend to be way overpriced.
Exercise equipment, wow! All those climber/stepper/treadmill combinations cost a fortune, and their targeted audiences, the way the commercials appear, are young people. Old farts like us wouldn't last 2 minutes on one of those expensive contraptions.
But what the Hell do I know - I'm just an old fart!

Gary