I'm thinking that when customers are rude towards me and they are the only table in the restaurant I'll purposely turn on heavy metal music or something similar compared to our casual 60's genre music in the hope that they won't like it and will leave the restaurant quicker.
How would you feel if it worked and they left?
I think I'd feel relieved that they were gone.
Blasting loud music is an immature way of dealing with rude customers. You're in the service industry so you'll have to deal politely with rude customers sometimes.
But it's so much easier to just turn on the music really loud.
I understand that it's easier, but it's not the right way to deal with the situation because it's unprofessional and childish. You'll either have to deal with rude people or you could ask one of your coworkers to take over for you.