Most supervisors don't just sit around barking orders -- they actually do some of the work. They're still mgmt.<quoted text>
When I am the only one on bar all day (on a day when I am not running the shift and have no management duties - yes, I should get a share of tips) and on days when I am running the shift, I am still serving customers, etc.
Like I said up front, if SB wants you to perform mgmt tasks, they should pay you accordingly. That you think you should get a slice of the tips suggests that they are not.