Casio does make some models in more than once location. Having owned models made in Thailand and China I can't detect any difference.
The new #1 Casio Plant is now open in Thailand. They produce 700,000 G-Shocks monthly. You'll see a lot more 'Made in Thailand' soonStick with made in China. Send your watch back and ask for another one. Most of the G-Shocks are now made in China (at least 95% of them). You are going to have to deal with that. The good old days of when Casio made their watches in Japan is long gone. Everything is made in China nowadays whether you like it or not.
This might be the case in some instances but I have a made in Japan GX56 and a made in Thailand GX56 and I paid exactly the same for both from the same source.The same watch made in Japan will cost like 25% more because manpower, taxes, shipping... from Japan are generally much higher than most of other countries.