Samantha Hoopes Ass Out at Juice Bar ... Is That On the Menu?!

Here's Sports Illustrated model Samantha Hoopes ordering some juice at Earth Bar in West Hollywood ... with her entire perfectly sculpted ass hanging out of her shorts.

Hoopes is adamant she was properly clothed -- "No I'm not in my underwear it's call motivation to work out & I just came from working out #donthatemyassismallenoughtoweartheseshorts."