Where did you buy the tires? I'd contact them about a return. I suppose it's hard to prove you didn't overinflate them, but they probably sell tons of cheap tires and odds are you won't be the only one with this gripe. Ultimately the message needs to get back to the mfr. but they'll probably hear that loudest if their distributors start complaining.

I've never thought about it before - do tires have a batch number?