What’s with the bike rims?
California should go green...soylent green.
Those are from the bikes they stole the front wheel off of. When people lock up their bikes they usually run a cable/U lock around the frame/rear wheel neglecting the front wheel. The wheels are then sold for cash for drugs/liquor. Sometimes a real moron only secures the front wheel. Now the homeless guy has a complete bike to sell/ride with the wheel from a previous theft replacing the wheel that he left when got the rest of another bike. They also steal bike seats. Most modern 10-18 speed bikes have quick release clamps allowing this.