If you order a beer at the grub stop I will politely walk over to you and ask you to hand me your keys. If you do I'll hand you my business card so that you and I can make the necessary arrangements. If you don't I'll get back on my ride and do the lone wolf thing, after paying my bill of course.
I think you'd be hard pressed to find anyone who would surrender their keys after a single drink. Many people make a personal decision not ride if they've consumed any alcohol whatsoever, myself being one of them, but I don't really think its appropriate for you to request someone not ride after a single beer. Not saying I condone the behavior, just saying its not your responsibility to tell others how to handle themselves.
In all seriousness, I will drink 1-2 beer and still ride assuming I've had sufficient time for the alcohol to work its way out of my system, but typically no more than 1 standard size beer. I will extend it to two if I'll be somewhere for like 2+ hours.
That's his decision.

