You, like most of the anti-firearm brigade, have never registered a legal hand-gun in Thailand.
It is a long, cumbersome, exercise in bureaucratic paper-shuffling. As well, hand-guns cost 5 times what they cost in the US. The average Thai doesn't have an extra 90K to 120K of disposable income to buy a legally purchased firearm. Thailand's gun laws are strict, and if you get caught with an unregistered firearm it's hefty fines and possible prison time.
Now - the availability of black market firearms? That's a different animal as I'm well aware that they are available and affordable. But saying the gun laws are pathetic. You have no idea what you're talking about. Get caught with a black market firearm and you are in a world of hurt. Get caught wielding your registered firearm in public and you are in a world of hurt.