Coming from Japan to Thailand 15 years ago, the state of the roads here was lamentable, and many of the streets/rural highways in the Issan region and around our city weren’t even paved – or had big enough holes to break wheels and axles, a common sight back then.
I used to go on university trips every term and we would often take the uni bus or minivans on long road trips, ostensibly for work, but more just to get out and travel. This was always a nice perk for government university work, because we could often take the whole family, as well. It also made me very aware of the lack of highway rest stops in Thailand.
Actually, the default highway rest stop in Thailand is fulfilled by large gas station facilities, most notably those run by the PTT group. PTT stations come in all sizes, from a few pumps and a convenience store to larger mini mall-type complexes. However, on the toll roads around Bangkok and central Thailand, there are a few privately run rest stops, most notably the huge one between Bangkok and Chonburi located here: ศูนย์บริการทางหลวง กรุงเทพ-ชลบุรี มอเตอร์เวย์ ขาออก. That ones been around as long as I can remember, and it’s huge (long, actually) and chaotic. It’s also got the most foreign food shops of any highway rest stop in Thailand, with a lot of western fast food joints like BK, McD’s, KFC (maybe even 2 branches IIRC), Indian food, pho, dim sum, sushi, etc. As a side note, it’s also very easy to miss the turnoff if you are speeding along the toll road there.
On our recent trip to Hua Hin, we happened along another private rest stop in Samut Sakhon called Porto Go. It was not as big as the rest stop mentioned above, but it was newer and cleaner (there’s also one in Ayutthaya, apparently). These new rest stops with clean facilities make road trips a lot more convenient than they used to be!