Very lame post, should of had that worked out before you got there, but like alot have said go the bar flash the cash they will have it spent for you in know time.
You can use ATM'S there but Don't get to much laos money (Kip) as most exchanges don't like trading with it, so you might end up being stuck with a lot of Kip thats useless anywhere else.
My partner was denied entry to Australia on the first attempt and I went through Siam legal I sent them a scaithing email. Because they left photo's and information out, they agreed to reapply and it was approved.
The grounds for the first attempt denial, were
1) they doubt she was in a 4year relationship with me.
2) her thailand ties were not strong. Example, family, relatives, children,job,bank commitments,assests,
3) Doubt she would return to thailand at the end of the Visa.
if you know anything about thailand you would realise it's quite normal to see an age gap between the foreigners and there thai partners, unless you live under a rock. And at a guess I would say the majority of males on this site are older than there partners, so I don't really see the point of your comment, unless you like to try and shame or embarrass people for no reason.