Could AS have liquor on board if they didn't have a proper liquor license?

Not sure about airlines but some states have a service license as well for mixing and serving alcohol. Here is Oregon's:

A service permit is for:
A server (waitstaff, bartender, manager, etc,) working at a business that allows customers to drink alcohol on the premises (like a restaurant, bar, tavern, winery, temporary special event license, etc.) to mix, sell, or serve alcohol.