I'm pretty sure we can all agree that the black population in each state has no effect on beer excise taxes.
Excise taxes are a function of which politicians suggest a target for the excise tax, how much they think they can get away with, how substantial lobbying efforts are against it, how badly politicians want to deter the behavior and how desperate the population is to stand up against the tax and do it anyway. I'm sure some political scientist has written a more specific formula, but that's essentially the factors you're looking at.
In some of the states, as discussed above, the big breweries have substantial positions and don't want to be taxed out of profits so they will spend the money to keep beer taxes from rising. Some states have historically low excise taxes, some have low taxes overall. Some states love their excise taxes. Some of the more conservative states enjoy a large religious presence that is anti-alcohol and believe excise taxes will minimize consumption (specifically looking at OK, MS and AL).
Overall, it's difficult to look at a snapshot of information that isn't entirely complete on the specific excise taxes and try to determine why fifty different sovereign entities made the decisions they made over decades.