[Silent Bob]

Levi, first your complaint is moot with expedia because their job is to sell tickets not keep track of what's in your passport. 2nd - you've traveled to bangkok before and you state you have a visa, was the visa expired? If you have a visa then they cannot make you buy a return, unless of course you actually need it. 3) If this ever happens, ask for a "Timatic copy" of this rule (Learned this from a Brazil excursion... and also PHX and others have stated this, so I read, I learn). That way you can show this to customs, though that might open up a can of worms you might not want opened.

Finally, it's ALWAYS better safe than sorry. You don't wanna be deported for something as simple as a ticket that could have kept your butt in the country as opposed to being escorted right back out of it.