My bike shop owner pal once explained to me why certain of their customers came in every 3 months for new tubes. It was because that was how long it took for the tire pressure to drop to the point where the tires suffered pinch flats, which required both tubes to be replaced.

My pal once got bold enough to ask one such repeat customer why they didn't just buy a pump and regularly inflate their tires. The incredulous response by the customer was they could just come in to the shop to get the tubes replaced, and tires re-inflated. It's a living, I guess.

If someone ever thinks that working in a bike shop is an adventure filled with working on cutting-edge tech and servicing high-performance customers.... well it isn't. Most of the work is tedious repetitive stupid crap like this.

I've also wondered why I regularly find 30-year old bikes in garage sales which were only ridden 3-months from shop floor to hanging in the rafters. Same reason: tires became deflated, then pinch flats, and owners used this as the excuse to finish with the bike phase thing once and forever.