Disclaimer: I have never stolen from a store either.

Here's a perfectly evil idea. Pay for one or two items, walk out with five. They call you back up to demagnetize the strip again, or simply let you go though. When the alarm fires again, they will just think it is malfunctioning. Stores will not harass customers if they actually paid money.

Of course you are not outright stealing from the store if you pay some money (and get a huge discount), but it is a curiosity that always intrigued me. Basically you would want to play on the good natures of people, the ideals of customer service, and the detector "crying wolf".

Another idea would be to carry a magnetic stripe in with you. No one would suspect you if you beeped on the way in. Just play it casual. This occured to me after hearing that certain types of Motorola security badges actually trigger the doors of certain places. Strange as it may seem, it could (and has) happened before. Fast talking, and the desire only to steal once would work best there.

All in all, don't steal. However, it's always fun to try to find clever ways to exploit the system. One of the biggest loses to retail company profits is something called "shrink". One of the leading causes of shrink is employee theft. Inside jobs. People walking out with stuff, or not ringing items in. Most people would know how to break into their own store, or steal something from their own workplace. Ask someone who works someplace in retail. Most people think where they work is the least secure place on earth.