There may be many different approaches to the idea of serving your customer base, but one thing is probably universally applicable: treat them well. However you interpret that, it seems pretty fundamental. You wouldn't want your outbound call center to suddenly hang up on your clients without warning, just as you wouldn't want to throw visitors to a live store out on the curb.
That's what happened recently at a North Carolina restaurant called Hops, according to Business Insider. To be fair, the restaurant was being shut down, apparently due to property rights issues, and the source reports that they are unlikely to welcome business again any time soon. It also appears that checks were settled and customer needs taken care of before they were asked to leave.
Still, this can be seen as a bit of an abrupt ending to an evening, and customers likely won't forget that. Even though larger forces will always be out of your business' control, your answering service or other customer-facing arm can sometimes turn moments like this into effortless experiences rather than awkward interruptions.
To do that, it may be best to partner with a company that is skilled in these kinds of interactions in a way that eases customer concerns. You want your patrons to be confident about whatever service you're providing, and a reassuring voice that doesn't dismiss them without a firm reason can be just what you need to maintain a well-liked profile among your fans.