The article “Cambridge cafes are closing earlier and night owls are not happy’’ (Food, Sept. 27) identifies a real problem, but there is a simple solution. It’s called a cover charge.

A cafe could charge $5, or whatever is necessary to cover costs, to any customer wishing to stay past 10 p.m. The business could apply the cover charge to a customer’s food-and-drink bill. Also helpful would be a sign explaining the reasons for the cover charge — a combination of a higher Massachusetts minimum wage and the fact that many late-evening customers linger without buying much. After all, this is Cambridge, and the vast majority of people here have supported increasing the minimum wage.

This is not just about coffeehouses. My wife and I find it hard to find a Cambridge restaurant that is open when we get out of a show at 10 or 11 on a weekend night.

Peter F. Ash

Bedford