Many servers and bartenders who have lost work amid the coronavirus outbreak are now contending with a challenging economic reality: how to make up for lost tips.

Take Ian Prebo. On a good night, Mr. Prebo was making $400 in tips bartending at Seattle’s Blue Moon Tavern, which closed this month after a patron caught Covid-19. Since then, like many bars and restaurants across the country, Blue Moon Tavern—which can’t provide takeout or delivery—has remained shut.

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