Here's the problem with trying to be everything to everybody, you end up being nobody to anybody.

My Ducati Story:- For the people who have known me for a while you will know that I have a passion for motorcycles. But im a FAN of Ducati's. Ever since a work colleague rumbled into the yard on his brand new Ducati red 748e I knew i had to have one. In fact I visited the Ducati shop that very afternoon on my way back from work and laid down the deposit for a brand spanking new 748s ( with the marchesini wheels ). Whilst I was at it I went crazy and ordered the carbon Termignoni exhausts. Gibber Gibber ( see I even talk like a FAN )
of course going to the Ducati Store was like taking a child to Disney. I felt about 10 years old and it was Christmas! It helped that my parents weren't there saying No! although the bank manager wasn't completely happy and my Mum cried when I took it home!
Anyway I'm going off topic, the point is that when your a fan you talk about your passion, and if you want to attract and keep fans of your restaurant, products or services, then the more specific and focussed you get, the fans you  do attract, will be even more passionate about what you create. Of course having fans helps on many fronts.

e.g If your speciality is fish, then your better off being the best damn fish restaurant around, with signature fish dishes!

When it comes to food, the principle of drilling down into a Niche holds true. If your focussed on one particular area, lets use the fish example, your skills will improve, your product will improve, and you will attract attention from the influencers who love fish. Im going to do a whole show on influencers very shortly.

[leverage tip] Finding a fan who already has an audience can significantly boost your exposure to other fans!!!!

Fans are much more likely to share your products and services ( make it easy for them by giving social links ). Fans are much more likely to talk about your product to their friends and family. And if you've done your job right, they will introduce you into the equation and that means more referrals for your business.