Ditto about the maids. Bad idea.
If you are in a motel on the ground floor, or a high rise facing another one, you can have sex with the curtains open and the lights on.
As far as the adult book store goes, I think you are on fairly safe ground, depending on how wild you want to get. If you stroll around with your wife's shirt unbuttoned, you should have no problems. If you start to fool around, you will draw an audience. You must make clear to the guys who will gather around what your limits are: "look, but don't touch. If you don't respect our limits, we leave. Show's over." In all the bookstores and movie theater my wife and I have played in, the guys have respected our limits.
Check out the video "preview booths". Some have "glory holes" others have controllable windows between the booths. You can easily control the situation.
You might try an adult theater. Some theaters are more couple friendly than others. There might be one in your area. Check the database at
http://dremiliolizardo.blogspot.com/ for possible listings.
Have fun!