No, playing the lottery is not wrong. As the OP said, it is a few bucks a week. A person can spend $5 on lottery tickets or he could spend it on beer. Which is better? Why is no one questioning the beer purchase but they question the lottery tickets purchase?
The only reason that they say gambling is wrong is because of that scripture in Isaiah about the god of good luck.
but the God of good luck is Jehovah. They don't even know what luck is.
This is just more superstition that JWs have taken on and adhere to without thinking it through.