This is a pretty typical rig in Thailand. This nice couple rides around everyday stopping every now and then to yell, "Som Tam!," "Gai Yang!," providing a valuable service to the community in the smallish Gulf of Siam place where they live.
One can't help but notice the propane bottle up front, providing a nice place to cook larb, an Isan dish made of ground pork, pig skin, some vegetables, a little pig blood, and some God knows what, but it's delicious. A the back, out of sight, is a charcoal grill for cooking chicken on sticks, or, more accurately, in this case, the less agreeable and cheaper pieces of a chicken pressed between a split piece of bamboo. The wife makes Som Tam, the "spicy papaya salad" that you may have seen on Thai menus in L.A. and elsewhere. It's all delicious by the way, from personal experience.
One day I saw them traipsing their daughter along on their rounds, oblivious to the danger of riding around on a motor-cyclized-restaurant including two hot cooking areas.