I'd pretty sure certain restaurants and bars bump up the volume purely so patrons cannot have a conversation and can only focus on eating and drinking.
Most of my restaurant trips are to enjoy a meal with friends or family, and talk. I wonder the logic.
Also the modern restaurant/bar interior is all tile and other hard surfaces: very noisy. This is partly for sanitary reasons but also to encourage people to eat and get out.
it turns out that rising real estate costs hit everybody and now everyone is trying to optimize every last dollar to make rent.
Encourages me to get out and not come back. I don't return to noisy places.