It is a visa for a Tourist no matter if you call it a non-visa or a Tourist Visa. The reason it matters to me is all the freaks on here that Criticize everything that isn't "Just So" Worded. And then there are the creeps that criticize anyone that asks a question as though people should have already read through EVER post in the group to see if there is an answer SOMEWHERE to the question. And you are treating me just like those a-holes because I said "non-o" instead of "non visa" (as if Thailand doesn't approve entry into the country with a stamp in your passport that is just like any "visa" stamp).
Do you get a "visa stamp" in your passport?? YES! Do you think what we call it will make a difference when someone walks through immigration upon arriving at the airport in Thailand.
Depending on what country you are from, you can come into Thailand on a 60 day non-o visa for tourism (you get it at airport when you arrive). Once in Thailand then I would consult a Visa agent (there are many businesses "Visa Agent" check with a couple of them) and they can help you with the particulars of setting up a DTV if you need. The 60 day "tourism" visa can be extended another 30 days near the end of your 60 day entrance visa. Thai Visa Centre in Samut Prakan (about 15 minute drive from Suvarnabhumi Airport in Bangkok) is a knowledgeable and fair priced Visa Agent.
Depending on which country you are from and as long as there isn't something bad like being a criminal or extremely physically looking sick then you can get a 60 Day Visa Exempt for tourism when you go through immigration arrival at no cost. If you get turned away then stay in airport International terminal and contact that agent for their help
Doesn't make any sense they won't sell you a sim card and service. If you leave Thailand the next day they aren't out anything since you already paid. They don't reuse sim cards.