Only your community can tell you what they mean as a "teahouse" and "coffee shop." APAs Planners Advisory Service No. 491 found a definition for a teahouse in Galesburg, IL (A public house or restaurant where tea and light refreshments are served, generally during midday.) However, it sounds like a restaurant to me. The issue, if there really is one, is a matter of scale. Perhaps restaurants should be broken down into subcategories based on the intensity of business rather than cute names.