Most Christians I know believe that Christians are allowed by the bible to drink alcohol. But can a Christian be a bartender? Own a brewery? A winery? A distillery? Some people who think a Christian can drink tend to shy away from believing these other things. Why?
It's quite okay to go to a bar, order a beer, sit and drink it, play the juke box, but to pour the stuff is questionable. Some might object out of fear that such a person would only be helping people with their vices. But with Christians supposedly holding to higher standards of morality, I would think that these people would rather have Christians in those positions than non-Christians. They would have a larger influence against drunkenness and vice, according to their own theology. Why not be salt and light from behind the bar as opposed to just in the lounge?