So here is the legal definition of gambling:
Gambling is accepting, recording, or registering bets, or carrying on a policy game or any other lottery, or playing any game of chance, for money or other thing of value. Title 18, U.S.C., Sec. 1955, makes it a federal crime or offense for anyone to conduct an 'illegal gambling business. '
Our personal opinions of the definition or of the law are irrelevant.
Linden Labs isn't out to deprive anyone of anything. They're just trying to keep their business going and provide their users with a fun experience. I personally enjoy gachas. But if I have to choose between gachas and being able to log into Second Life, I'm picking SL.