Song length is tied to revenue and thus tied to the revenue model. 3 minute song is 20 songs per hour, 4 minute songs are 15 songs per hour, and 5 minute songs are 12 songs per hour. Not having a standard length song puts your revenue potential all over the map. This is not a concert hall.
If I wanted to play the songs that the dancers really wanted I would be asking over at the pink site. If a dancer is more worried about her preferences in music than the preferences of the customer she has already proven herself not to have the right kind of customer focus. Frankly I expect that when adding to the playlist in the future the dancers will be listened to. But it will be as something of a reward given after a couple of months tenure. Besides why should the dancer on stage have so much importance? Most of the revenue while she is on stage is actually being earned in the lap dance rooms. That a song will generate more follow on dances is more important to the revenue of the club than whether the dancer gets a couple of extra dollars stage-side.