Yes, You Should Still Tip 20% on Top of a Restaurant Service Charge | Bon Appétit

"An Indian-American sports bar in Los Angeles' Silverlake neighborhood whose owner added a conspicuously placed 19% service charge (not optional) and framed it with a brash menu note beneath the wings. The charge is listed above a tipping field; tipping is optional but encouraged and distributed among front-of-house staff, with a small portion of the service fee shared with cooks and management. The mandatory surcharge was introduced to boost worker pay without raising unaffordable hourly rates for a staff of more than 40, and management emphasizes finding and sticking to a fee structure that sustains both employees and the business." - ByMaggie Hennessy