True, but if a local Oregonian beer has a $49/bbl tax on it, and a beer trucked in from any other state or country only has a $2-$5/bbl tax on it, people can avoid the tax by purchasing beers brewed elsewhere. That will in turn drive down sales of beer brewed in Oregon and either put breweries out of business, or drive brewers out of state.
Also, if they look at homebrewing as lost income, they'll heavily tax and regulate or even eliminate legal homebrewing within Oregon.