Public DM'ing

Howdy folks - looking for others who have DM'd for public events where the tables are drop-in/drop-out and need some advice.

For what it's worth, I'm no spring chicken when it comes to 5e, I've been playing for ~9 years, with 3 or 4 of those years acting as a DM. That being said, all of my prior DM experience has been with various groups of friends in a setting where the players are consistent and building arcs + stories is as simple as talking to my players beforehand.

However, I recently have started volunteering at a local brewery who hosts once-a-month D&D nights, and so far it's been great the first 2 months. Up to this point though, I've only been running one-shots to get a feel for the players who attend. I would really like to start shifting into a longer-term campaign for this event, but I'm not sure how to handle the flux in players, where I could have a table of all new faces compared to the month prior.

Has anyone here been able to run a campaign successfully in this environment before? And if so, what are some tips/tricks I can take into account when trying to worldbuild for this type of setting? I'm so accustomed to taking liberties with player arcs because I've always been able to discuss things with my players beforehand, but this is new to me.

Thank you in advance for your help, fellow DM's!