It's very common to ask for adoption fees when legitimately rehoming animals. The fees help keep the animals safe- People value things they pay for more than those they get for free, and someone who has paid a little for the animal now not only has some cash in the game but has also has proven they have at least a minimal source of money to care for it with. It helps prevent impulsive pick ups of "free" pets that people either can't or won't pay for proper care of.
In the case of small animals, it also prevents them from going for more nefarious uses. People don't generally spend $20 on an animal they're going to use as snake food, whereas a "Free" hamster can easily meet that fate.
In SG, only licensed breeders, resellers (pet shops) and SPCA are allowed monetary exchange for hamsters. I think you mistook my post implying that all adoptions are sketchy.
You're right, fees are very common, and often abused for a quick buck. I get where you're coming from but as I've said, majority of the posts I see — not on HH — are of the same people repeatedly having hamsters up for adoption at a fee, and they aren't very well taken care of tbh. I should also clarify that I'm talking about those selling the babies, not the parents. I'd rather pay a breeder who's patient and takes good care of his/her hams, hence my question for a reliable one.
Not sure if I would totally agree that people who pay for their pets value them more, some hamsters/dogs/cats etc up for adoption were once bought too and abandoned or given up for less serious reasons. It happens.
IMHO, having a proper screening procedure would be better (meeting up, seeing the hamster's future dwellings). I would totally buy new bags of food and bedding in exchange to show sincerity — since I would be getting for mine anyway — it's still money out my pocket and I can make sure the hamsters left behind/parents get the supplies they need.
At the same time, think this could possibly deter unscrupulous breeders if their aim is money and not bedding or food.