It's not a visa but a stamp, that's why it's called a visa exemption. A visa is what you buy in a Thai consulate or embassy before you wing your way to Thailand.
it ain't called a visa but a "visa exemption." You don't have a visa if you didn't bought one in a Thai consulate before you came here. Extend your 45 visa free days, even if you only wanna stay 1 day longer. Avoid overstay and don't listen to all the crap peoples telling you. Enjoy your holidays.