That are probably the temple's public parking lot because it is in the temple's area of wall but for Thailand, public parking should be owned by anyone, it doesn't matter because anyone can use it especially the area's temple, market or department store, unless in the area is a restricted area or is only allowed to enter by designated persons such as school for student, apartment, goverment and military.

I couldn't believe it at first. But after looking at the photos, I found that it's really, may that temple is now cutting spece for renting out commercial.
You can check with this photo
https://www.img.in.th/image/t3v6u2