Orange county permits sale of alcholic beverages by bars and restaurants between 11a and 2a. The rule in Kissimmee is 9a to 2a. Unincorporated areas of Osceola County, the rule is 7a-2a.
Non-Incorporated areas can set their own rules. I don't know what the rules are for Reedy Creek (Bay Lake and Lake Buena Vista). Some parts of the country, not sure about Florida, have different hours for restaurants and bars. Might be the reason Disney is listing Oga's as a restaurant.
Disney can pretty much make their own rules.