However, if you are a private establishment or if you are having a private function, there is a gray area. According to the TABC, "It is legal to provide free alcoholic beverages without a permit. However, to be truly "free," it must be available to any adult who walks in the door and requests it. If alcoholic beverages are only available to paying customers, the assumption is that the cost of the alcohol is included in the price of the service. This constitutes a sale of alcoholic beverages, and a TABC permit would be required. When you provide the alcoholic beverage, there cannot be any expectation of receiving money. If the drinks will only be available to paying guests, then you will need a permit."
For charitable, religious or civic orgnizations, please refer to the TABC website for permit details. http://www.tabc.state.tx.us/faq/licensing.asp