some jobs... more than others. If an employer can find a programmer or sysadmin who can't get a job elsewhere because of poor sales skills, well, it sounds like they could either pay less or get someone with better technical skills than they could otherwise.
(That and my personal feeling? the guys who are 'always selling' are hard to deal with. I can handle maybe one day a week, if that, dealing with those folks.)
Seriously. Not everyone needs to be the team lead. The kid in the corner who is really good technically, who solves technical problems has a lot of value even if his or her social skills are poor.
I mean, sure, they'd be /more/ valuable with social skills, too... My whole point is that you can't get the perfect candidate. Quite often it makes sense to take a hit on social skills if it gets you someone who is better technically. (and sometimes the converse makes sense, too.)
I'm just saying, there is a place in the workplace for the introverts who don't interview or argue well. As an employer, if you only hire technical people who can get dates, well, you are limiting yourself.