Best Buy has a right to request you submit to a bag check at the door. You have a right to refuse. You can walk out right past them and they cannot detain you unless they put you under citizen's arrest. They do have a right to tell you to never come back since their store is private property. If they wrongfully detain you, you can sue for false arrest and you will win (assuming you didn't steal anything.)

Personally, I don't mind the bag check but I think it's important that people understand their rights in regards to things like that. We spend so much of our lives being bullied by people unnecessarily.

While I'm on the topic, I recently viewed an ACLU video regarding your rights when being searched by the police. I see this all the fucking time on Cops, so I know it happens. If you're hauling your sweet nugs around or whatever and you get pulled over and the cop asks you to search your car, just say no. Unless you're a total moron and you smoked up in your car and left your bong lying around, a search is totally voluntary. They can't detain you for an outrageously long time. Odds are they will be irate, give you a ticket for whatever they stopped you for, and drive off. The three important questions or things to say when dealing with the police are:

I do not consent to any searches.

Am I being detained or am I free to go?

I do not wish to answer any questions without my lawyer present.

Seriously, you have the right to remain silent for a fucking reason. Don't just throw it away because the cop said he'd help you out. Shut the fuck up and get a lawyer. The cops can't arrest you for not complying with a search request unless he/she sees that you're breaking the law. If you do get arrested without probable cause any fucking lawyer can get you off.

You do have to give your name and they can search your person for their own safety. Don't be a dick but don't offer yourself up to the cops.

I suggest everyone purchase the following video: