Not endorsing, but allowing is aimed at letting people feel like they aren't being handled like children by their employer, and, as alcohol is a very common component of social interaction in western culture, is meant to make it easier for workers to socialize and make friends with their colleagues. I'd imagine the reason for wanting that is something like that employees who are more connected with each other are more likely:

a) to want to stay at the company with their friends, less turnover

b) to be happier at work which is good for performance, recruiting, and makes them less likely to feel the need to rush out of the office whenever they can.

c) to efficiently organize themselves and find the right people to get things done if they know each other well

d) to be transparent to each other and reduce friction in communications

You might not ever have some beer or wine when you socialize with people, but for a huge number of people that's viewed as an integral part of socializing.

The amount of alcohol you consume doesn't really matter.

It's the behavior that is punishable regardless of whether you were drinking or not.

So when your high functioning alcoholic blows a .22 after taking out a telephone pole and hurting another driver, what do you do then?

What portion of responsibility will the victims attorney pin on you?

Zero. Don't drink and drive; It's the drinkers responsibility. Do you blame the liquor store? The state liquor laws?

Nope. Serving alcohol or providing a place to drink can make you liable.

That’s why you’re usually advised to get a liability policy for weddings and large parties.

Sleep deprivation affects cognitive ability. It affects everyone differently. It is sometimes involuntary, sometimes voluntary.

That said, how many hours' sleep the night before a day's work is acceptable?

> If you allow drinking at work, what BAC is ok?

Rules don't have to be written around BAC, they can be written around behavior or impairment.

(In fact, while they tend to also have a BAC cutoff for ease of proof, criminal drunk driving laws also are written around impairment, and corporate policy doesn't even have to worry about proof issues in at-will jurisdictions, because there is no proof requirement.)

Marijuana is now legal in California too. What standards apply there?

Don't be stoned out of your mind

> Marijuana is now legal in California too.

No, it's still against federal law, which covers California.