I've been in Thailand for 5 months every year for 9 years. I often land with no visa and get a visa exemption on arrival which lasts for 30 days and can then be extended for another 30 days. I then go to Vietnam and return to Thailand. On this trip, I have been here since last November and leave in two weeks. I DO NOT HAVE A VISA. So, no, I am not 'so wrong'.