Yes, but I recently had a rather curious experience at the Thai consulate in the US. Their web site states you need to show tickets in and out and a bank statement. I printed these out, but the receptionist handed back these documents before sending me to the visa window, so they were never considered. Perhaps the requirement was dropped and the website not updated. I do know that if you overstay your welcome, you will be fined per day you are late leaving the country.