Mobile Phone Offers = Gambling?

[surface]

I've been receiving some SMS spam recently, usually in Thai, that gives instructions to enter a certain number (or send an SMS) to be entered into a contest to win something. Usually they are 30 baht or so per entry, don't remember what the prizes were, but today when I checked my balance AIS included the same type of gambling in English to win a Honda Jazz "with Doraemon" (some kids cartoon?). "More Vote! More Chance!"

Before I assumed the money was just going into some shaddy spammers pockets, but this is from AIS (yes, I know, one in the same ).

How are they getting around the gambling laws?