It's not too difficult to light a bar counter scene with soft light when it's all done in medium and close shots, you usually put some large soft units behind the bar counter -- Kinos, Litemats, paper lanterns, etc. Looks great on faces. The main problem is usually just leaving room for the bartender to move back and forth to pour the drinks if you end up with c-stands behind the bar counter.
The challenging part is when you start with a wide shot that sees the whole bar counter and wall behind it and the ceiling above it -- and the camera dollies across the room into a close-up and you want that sort of soft key light. Then you pretty much have to install practicals that give you that soft light, and sometimes it looks odd design-wise to have fluorescent top lights over a bar, for example.
A lot of bars don't have any practical lights over the counter area, people are dimly lit by units over the back wall of bottles. And then it's a problem when the ceiling is smooth or has some historical tin cover with nothing to rig off of. I've scratched my head many times trying to figure out a way to light people at the bar counter for the wide master in a way that will allow me to then cheat some nice soft light on the close-ups without a major change in look.