[larrydavid]

Websites built entirely in Flash are horrible in most cases.

You also cut out a massive section of mobile users that can't use your site when on the go.

Check here for some tips specific to a restaurant site: http://www.better-restaurant-websites.com/

[dubfan]

Mobile compatibility can be extremely important depending on the type of restaurant and where it's located. On a website I did for a restaurant located in a tourist destination, mobile and tablet devices account for about 55% of all visits.