A new paint job costs money. It also takes time, and involves more people.
Most thieves are looking for something that they can sell on within hours. Most people who handle stolen goods are looking for an easy onward sale.

If you do a bad paint job, e.g. spray acrylic over enamel, or vise versa, you get crazing. This would require the bike to be fully stripped back before new paint. You can't just spray over the top of the old and get a nice finish. The same is true if you hand paint with a brush, it must be fully prepared.

The people who buy stolen bikes, probably know they are stolen, but they still don't want a crappy looking, or easily identifiable machine.

Hopefully the new registration, and need for original fapio will make it harder to sell on stolen vehicles.

In my old uni, there was a family that lived in the basement, at the entrance to the bike park. They managed it all.

Not sure how the GE algorithms work.
Maybe they map to the registered government office.

Check Apple maps, maybe it is somewhere outside Chengdu.
Or maybe just Nocandu

Try most Carrefour, near the bikes, sports goods, and kids toys. They used to have them.

Not pro gear, but protective.

Just a thought.
Most Cantonese restaurants I went to in Shenzhen and Shanghai only served dimsum in the mornings and/or afternoons, not at lunchtime or in the evening.

It will be worth checking the times. You must specifically ask 'what time?'. If you just ask, 'Do you...' the answer will be a simple 'yes'. Don't expect more details. Seriously, it is one of the annoying things about getting information here, people tend not to volunteer helpful additional information.