I agree with Ian.
If I had, say, 3 or 4 pints yesterday and came out of the pub and slipped on the ice and bust my wrist, would the nurse breathalyse me to ascertain whether it was "my fault"? Who would set the threshold, presumably, like drink-driving law, someone would have to decide what is a "safe" level of alcohol for everyone, to remove any personal or subjective decision-making by the medical staff. This of course would be unable to take individual tolerance into account. The so-called safe level for men/women's weekly allowance was plucked from thin air yet is constantly quoted by the medical profession, even though gps know that lots of blokes lie about their intake, and indeed may drink more themselves, without ill-effect.
As has been said this would be the start of a slippery slope, no doubt with little charges here and there eventually leading to the credit-check at the door. What if you didn't have any savings to draw on when faced with the bill, which would no doubt be in the thousands, would you be sued for the cost? Made to sell your house? Sell your kids?
Like smokers, drinkers have to be painted as "baddies", as we do something that some others disapprove of. Well I think people who choose to play or do physical sports and hobbies put themselves at (through their own choice rather than necessity) risk. They enjoy kicking a ball around, I enjoy a few pints.