A wine key to the eye isn't a pleasant experience, but if that's something you're worried about, you're probably holding it in the wrong direction...
You'll be on your feet for much of the day, probably in fancy-ish shoes so you'll want to watch out for calluses and whatnot, sore legs, etc. If you're irresponsible and partake in some of the wine yourself before driving home, you could be in the worst kind of physical danger, but that's not as much of a hazard of the job as much as it's a hazard of your own lack of good judgment.
Otherwise, as far as we can see, it's a pretty safe gig. Hey, a glass of wine a night might even extend your life expectancy.