Why are bars so pricey?

I know somebody will mention the additional expenses like labor, rent, licensing, etc. but the discrepancy is crazy.

At least in So-Cal, I can get a 30 rack of beer for roughly 20 bucks, but one beer at a bar will cost close to 10. A 30 rack for $20 would be $0.66 a beer, which is more than 10x less than a $7 beer at a bar.

For liquor it’s even worse. I’ve seen bacardi shots for also close to $10, but I can go to the store and get the entire bottle for $17, which has 40 shots.

What gives? The discrepancy is insane, and for me it’s not worth it at all. Sometimes you can find a good deal but outside happy hour I’d rather just get a few friends and drink together.