My Thai wife wants to do a border crossing with me at nong khai into Laos. If she uses her passport, will she have to enter into laos before being allowed back into Thailand? She basically just wants to cross the bridge while i do a visa hop. How about with id card?

If she gets stamped out of Thailand she would have to enter Laos to be stamped back into the country. No problem to enter Laos with her passport since she will get a free 30 day visa exempt entry.

Without a passport she would have to get a border pass (about 50 baht) to leave, enter Laos and return.