Major Tom
Thinks s/he gets paid by the post
I believe those sorts of discounts are fairly common. When I lived in Los Angeles, the El Pollo Loco restaurant next to my place of work gave 50% discounts to LAPD officers, while my place of work gave a 25% discount (which, considering the mark-up of the goods we sold, was a generous discount).I once took a course where we had to accompany the police on their nocturnal rounds. I learned that Tim Horton's routinely provides free coffee (though not donuts) to cops on the beat. They like to see the cops coming in as it keeps the criminals away.
Many retail businesses, understandably, like to have police officers as a regular presence.