Why would lack of taste in graphic design be even remotely related to lack of taste in food preparation?
It's like arguing you wouldn't trust a lawyer with a medical negligence case if they can't suture a wound.
Or you wouldn't trust a graphic designer with a restaurant logo if they can't make good scrambled eggs.
Do people even expect anything from “sports” grill?
This is assuming that the owner is also the chef, and exclusively concerned with cooking. Being a restaurateur is a multi-disciplinary job. The owner's job is literally to have good taste in all areas of the restaurant business: food, interior design, hospitality, branding and marketing, etc. No one is saying that they have to be a graphic designer. The obvious answer here was to have the good sense to hire a local college art student for like $300 to make an endearing and meaningful logo.