:powerlevel

oubling up on this. I work at a gold standard vet and ideally we wait 4 to 6 months because research states that they should be fully mature and developed by that stage. HOWEVER you are right in saying that shelters will desex as young as 8 weeks because of the influx of cats vs. the number of people adopting them. People want kittens but they don't want the responsibility of desexing them.
A pet store though? I highly doubt they would front the cost of desexing an animal. It would cost more than the price of selling the cat, and animal welfare is not the primary concern of a pet store. The only case I could see this as a possibility for would be a breeder who doesn't want someone to breed from their line of cats, which is obviously not the case.
Sorry for PL!!