Who doesn't like watching a movie in a real movie theater? The massive screen, the in-your-face sound, moving seats, annoying teenagers, giant sodas, and the popcorn... oh, the popcorn! Boise has some really great theaters, too. One has an IMAX screen, several serve alcohol, some have 4DX, and others have seats so comfortable you know you'll have to wake your dad up before he starts snoring during a quiet part. We can all agree that watching a movie in a theater is a far superior experience than watching a movie at home on your 50-inch flat screen, except for the price.
Yes, we love the food and snacks, but an evening at the movies can be expensive. That's why, while we've never tried it, we've all thought about doing something shady. What would happen if, once your movie ended, you walked into the theater down the hall that was just starting another film? Could you be kicked out? Could you be banned for life? Could you be arrested?
The answer, like so many other things, is a little subjective. It depends on where in Idaho you do the movie hopping and what that jurisdiction's interpretation of theft is. Some states have laws that say you can only be charged admission once unless you leave the facility. For example, suppose you enter a museum but only pay for some exhibits. In that case, you are forced to exit back to the lobby in front of the point of purchase before being able to continue into the premium exhibits. Most movie theaters are not designed this way; therefore, in those states, while it's frowned upon and certainly not right, it isn't illegal to just walk to the next theater and sit down unless this theater has assigned seats, which is why most movie theater companies have switched to this model.
While Idaho does not have a law specific to movie theaters, stealing is against the law. If the theater company calls the police, you could be cited for stealing. Since the value of the admission ticket isn't very high, the police may not see it as worth making an arrest; they could if they wanted to. The theater will likely ban you for a period that they view worthy.
It may be exciting to sneak into a place you are not supposed to be. Still, it is wrong, potentially illegal, and ultimately not worth the risk, considering you'd only be saving $12.