So if Vincent had any bad vices what do you think they'd be? Smoking like Cid? Drinking (after all there was a glass of wine in his room 1st FMV)? Both? If you think he has no vices then explain the reasoning.
Well... aboard the Shera, Cid says to Vincent that the two of them should go for a couple of cold ones, just like old times, once the fighting's over - so we know Vincent enjoys a drink.