A great loophole I have found is being in the Air National Guard. In basic training there is nothing you can do about it, they shave your head. But as @woodcutter says, it’s better that way. But once you’re done with training it’s nice to be able to grow it out again. I serve one weekend a month so in b/t that time I can grow out my hair, grow a goatee etc. Just when my weekend rolls around, I trim it down to the specified length.