I'd be pissed if I applied for another job and was turned down purely because of my previous employer. But I'm not phased by avoiding cold calls. I still get loads of emails trying to recruit me and they're mostly annoying. If I decide to switch jobs, it'll be because I initiate it, not because of HR reps phoning me.
If you were around during the last dot-com boom, you may remember the ridiculous poaching that went on, startups offering insane signing bonuses and other perks, employees changing jobs after only a few months on the job. I worked for a company once that had $100+ million in Softbank funding, and funneled a huge amount of it through headhunters which received a bounty on each hire, and were incentived to bribe prospects to quit their current job.
I'm not sure this is healthy for the industry as a whole. There's already an apparent bubble in asset prices and cost of living in the Bay Area, and while it seems good for some tech workers in the short term to have salaries pumped through the roof, I'm not sure it's good for the overall tech economy, or the economy in general.
I'm somewhat sympathetic to the notion that companies want to avoid aggressive and invasive poaching on each other's workforces, it could turn into mutually assured destruction. If I had a startup, I'd be pissed of someone came along (and poached my employees instead of an acqui-hire) that I spent significant amounts of resources recruiting and training.
To read some of the press articles, you'd think this was the Grapes of Wrath or something, that poor tech workers, the ones who drive around in luxury busses and pay $3000-5000/mo for studio apartments in SF, are woefully under compensated. I wonder if this was a story about Goldman Sachs and JP Morgan conspiring to keep down the compensation of Wall Street money managers through no poach agreements, we'd have the same coverage.
Here's analogy. Let's say there is an employee marketplace. Employers list jobs for offer and salary. Employees list skills, availability, and asking salary. If the employers don't conspire to artificially restrict the offers and salary prices listed, would we say this is a competitive market with no price fixing?
Ok, now let's say that besides listing the jobs and prices, Employers activity solicit buyers. With stocks regulated because of issues (http://www.sec.gov/answers/cold.htm). But let's say employers cold call the employees and tell them to 'buy' a particular offer. Then at some point, the companies cease using sales forces to go out and cold call people to buy these offers. Instead, employees must come to the market of their own accord and bid on them. Is this really price fixing?
If all brokers stopped calling you trying to get you to "Buy XYZW", you wouldn't consider them trying to manipulate the price of XYWZ.