I don't usually feel terribly comfortable taking advantage of Microsoft employee discounts at local businesses. There are a lot of these, and employees and their spouses carry around a "Prime card" to identify themselves as such. I can get 10% off at the salon, or buy one entrée get one free at the restaurant. But it just feels weird. It's some physical reminder that I'm getting paid more than the person accepting the card, and that's unpleasant.
But in the end, it's just business. There are tens of thousands of Microsoft employees in the area. We talk, we email, and there's a lot of word of mouth that goes on. Any little thing to get more Microsoft employees to come to your establishment is very good for business.