If you do not show up before the last day mentioned in the stamp in your passport, the fine is 500 Thb a day with a maximum of 20.000 Thb and eventually deported and black listed.
Not about to show or not, but for an old bastard living in rural Thailand not visiting any bar or restaurant the rule is minimum 800.000 Thb for 1 year and for a young broke having the best time of his live, only needs 20.000 to live 1 year in Thailand. i now the prices, but that 20k is not going to last very long.
20k is for 30 days visa exempt, 20K is for 90 days with a tourist visa and 20K is for 1 year out of an ED visa. For the Visa Exempt I can understand, 20K for 1 month living is good, but to live 1 year inside Thailand on a budget of 20K is ridiculous .