Meaning that if you have one beer, you aren't allowed to race for the rest of the day? Wow! I've had races where they provided alcohol at aid stations. (Not a big glass, mind you.)
It's really a CYA exercise. People drink 'freely' at there own support stations. Most of our guys had a beer after lap three (and or 4). They are just being prudent in case some dumb-ass gets drunk and hurts himself or someone else, they can at least fall back on the posted rules.
I did not see a single person that I thought was abusing the 'lack of enforcement' outside of the serving area.