If one looks closely at these altars, it is generally not the image of a Buddha that receives the prayers. Usually they are mythological creatures, photos of ancestors, or Hindu images, particularly Brahma, the four faced Hindu god of creation or Ganesh, the elephant-headed god of success, as Hinduism continues to exert a strong influence. Even Vishnu, the supreme Hindu deity, is embedded in the official Thai government seal. These are the most popular altars outside of Buddhist temples. Interestingly, they are often seen at street intersections, so that--according to a Thai friend--they act as a type of traffic control: Drivers slow to pay their respects.
It is indoors, or if outdoors, on the grounds of temples, where images of the Buddha are worshipped. Well, there and on the dashboards of taxis. The religious practice of Thai Buddhists is complex, and offers a fascinating look into the culture of this calm and accepting people. Don't try to figure it out: The Thais will laugh and tell you that they themselves cannot explain it. (To read more about Thai spirit houses, go to www.chiangmai-chiangrai.com/spirit_house.html)