They are usually attractive women that are (depending on the place) scantily clad that are sent out on busy nights to sell pre-mixed shots(IE shooters) in tubes like these...

Actually a decent money maker as most are low spirit to mixer ratios. Sell them for a few dollars each to the drunks who are paying more for then than a regular sized drink would cost. All they do is pass them out and collect the money. Shot girls can make decent cash but the real money is still behind the bar.
But like I said you want a shot girl that the customers are going to like and I don't think the primitive fits the bill. A five minute interview would usually indicate that she has a face for radio.
Hold on one moment, all this put down for the bar girls is just not fair.
I have had in the past life found some wonderfully smart bartenders and servers. I have seen young girls take orders from tables of 12 all different and at rush hour, no pad of paper, just from memory who ordered what, the price, and get the orders correct. How do they do that ????
My favorite bartender/ waitress worked up the road and when she looked out the window and saw our Jeep pull in, had our favorite table ready for us with our cocktails waiting when we walked in the door.
Sad this was a neighborhood hang out, closed off bar and eating section for smokers. When the LAW changed the smokers not allowed, the restaurant closed down due that 80% of their customers were smokers.
These small bars that served food hired the local people that was so much like the TV sit com filmed in Boston, when you walked in everyone knew your name, they are gone now, but, if one owns a bar and grill, it is better to hire smart people then a beautiful bubble head that cannot make change.