I think there are different solutions depending on the knowledge of the staff and business owner. For a business that just wants to accept sats without thinking about it, something like coinos makes sense.
I assume for specifically Bitcoin bars, because the staff tend to be bitcoiners so they're more nimble to changing up their setup and doing things like node running.
Edit: actually coinos seems to have grown a lot since last I checked and it looks slick even for hardcore bitcoiners