You're making an unfounded assumption. Unless something has changed or they're requiring it, but for whatever reason they don't want to tell anybody, there is no published requirement for Thais to show proof of where they live. Have you seen anything that says Thais will have to prove their residence?
Just to counter your argument about a Thai's ID card showing he comes from another province even though he resides in Pattaya, how about a Thai whose home province is Chonburi, comes from Pattaya, but has been living and working in another province for years, and now he's coming to Pattaya just to visit family or whatever. His ID card will show he comes from Pattaya, even though he doesn't live in Pattaya.
Until we know what is required of Thais, I suggest we stop making assumptions and speculating.