Sure, the city might have a problem, but that shouldn’t be your customers’ problem.
Every day, we must adapt to the cards we’re dealt.
Rather than “We are not serving tap water, sodas or brewed tea today” and taking what might be perceived as a political shot at the city (the same one who does their next restaurant inspection?), a customer-centered management team could have called Culligan (et al) to get all the restaurant-approved water they’d need to provide glasses of water and brewed tea.
If you’re Culligan, there’s a win-win there.
Perhaps you can’t easily and quickly alter the water supply for a soda dispensing system, but that still doesn’t require a sign.
A quick look at last week’s sales totals from the register would have told them that they sell 430 sodas per day on average and run over to Costco or Sam’s (or called their normal supplier) for a canned/bottled supply that would span the gap for them.
The next work day, they could consult with their soda mix supplier and explain the situation further, ask for advice on water supply adaptation and then contact their plumber to arrange for a way to feed the third-party water into their soda system. Or they simply could have adapted using pre-mix, though that would probably be too much of an interference to the restaurant’s workflow.
Instead, they chose to sell no soda and no tea (both high profit margin items) and take a shot at the city.
Maybe the city needed a smack, but the place to do that is at the city offices, at a council meeting and worst case, in the local press.
Using your customers as pawns in that game makes for a losing battle, especially when they are standing at your front door with their wallets and purses open.
PS: Interesting that coffee wasn’t mentioned on that sign. Might be because many places use high-tech water filtration systems for their coffee water supply lines. I wonder if a non-franchise restaurant would have reacted the same way.