"Some communities have issues of morality regarding promoting the drinking of alcohol or concerns regarding the kinds of behavior that can come from drinking too much," notes Kyle-Beth Hilfer, an advertising and marketing attorney with the New York-based law firm Collen IP.
Having so many different rules means bar owners and restaurateurs need to keep up with changes in the laws and read existing statutes carefully, says Hilfer.
Some states allow happy hours, but ban advertising them. Oregon, on the other hand, is OK with bars advertising general happy hours but not specific price discounts. Utah outlawed happy hours in 2011.
Advertising also can be tricky. A state may OK advertising happy hour specials, but going beyond the simple price and inviting customers to "lose weight at our low-carb beer happy hour," could be subject to regulation by state alcohol beverage officials, Hilfer explains. She recommends that proprietors of venues that serve alcohol and have happy hours have a lawyer vet advertising copy.
Social media has added a new twist to the mix. In Virginia, it's illegal for bars and restaurants to advertise happy hours in electronic media, radio, TV and the Internet, a law that goes back to 1984, long before Twitter had left the nest. This year, Virginia legislators considered changing the rules, though the bill ultimately was withdrawn, partly due to concerns about underage drinking.
This wasn't Virginia's first time to update old laws. In 2006, a tapas restaurant was cited for serving sangria because its recipe, a mix of red wine, brandy and fruit, violated a 1934 law prohibiting the mixing of wine or beer and spirits.
In 2008, lawmakers passed a bill sanctioning sangria.