Day 36 in The Beat Handbook: 100 Days of Kerouactions references the below passage from On The Road.
This passage points out an important aspect of bar etiquette. Many local bars are frequented by "regulars," who may or may not be too friendly to new faces ("tourists," as Jack refers to them). If you're lucky enough to become a regular somewhere (and the exact process for doing that - if it is even possible - varies from bar to bar), I hope you'll remember that you weren't always a regular, and maybe you'll choose to be compassionate toward newbies.
As with everything, it's up to you.