I’ve heard that said, and it could be right. On the other hand, you’re more likely to pay for a dessert or more beer if you’re not in a hurry to get back to the peace and quiet of your child-filled home.
My alternate theory is that the people working in many restaurants have had loud music turned on constantly since they were young children. They can’t imagine people’s wanting to just talk to one another (that’s why there are all the televisions in the restaurant, too), and their hearing is damaged so that they don’t know how loud it is to people who can actually hear.
I agree that the “background” noise has gotten too loud. I have left clothing stores b/c I can't stand the noise.