The problem is bikes are so cheap now that most won't pay for new tires and tubes or do the work themselves. It's easier to toss and go to Wally World and pick up a brand spanking new MTB or BMX for $50-100. There are and will be tons of these in the dump.

I saw what most would think a nice MTB for $69 or $79 on special around the holidays. There is just no money or value to them once the consumables go or they start having shifting issues. Kinda sad when you think about.