I am a U.S citizen living in Mexico. My wife is a Mexican citizen and has no plans to work in the U.S. We just want to travel. Can I just get a tourist visa for her? We don't need the residence visa as we have no plans to work or live in the U.S.
Yes you can. I and my wife are in the exact same position (except her nationality) and she was given a 10 year multi-visit visa no problem. There are many expats around the world who are in this position and who visit the U.S. all the time with the non-citizen spouses in tow.
The embassy will most likely ask for evidence of her stability in Mexico to establish that she is not an overstay risk. This is normally done by submitting bank account details, letters from work or school, contact details for people she knows or will be visiting in the US, and conducting an interview at the embassy. If she is unemployed and doesn't have much money in the bank, there could be difficulty.
There could also be issues if they suspect she is visiting to marry you. They will most likely ask her to swear she isn't visiting to marry, and if you do they could use her statement to invalidate the marriage visa application and deport her anyway. I'm not implying that you would, but it is best to not try to game the system.