I think people are as smart as they need to be. You don't need to be able to summarize tabular data if you work at a fast food shop (e.g. as a waiter).
And it definitely has to do with the circles you hang around in. As a programmer you're more likely to be in a rather smart circle.
dono. I've met more than a few smart people working in the service industry. (I've hired a few, too, with good results.)
Personally, when I hire someone, I rate hobby experience as more desirable than paid experience. I can give you paid experience. At least for SysAdmins, I can train you in all the gotchas of production. But I can't make you like it.
And it definitely has to do with the circles you hang around in. As a programmer you're more likely to be in a rather smart circle.