In fact, a situation where employers and employees are in opposition to each other, rather than working together, is possibly one of the leading factors that can lead to data theft. At the end of the article, it is reported that "about 42% of respondents said their companies' security is non-existent, not strong enough, the wrong type, or too restrictive." It's likely that they had little to no input into the implementation of that security.
I'm certainly not arguing that nobody steals data from their workplace for financial gain or to get an "in" with a new company. (Or to foment a political coup.) But I would suspect, from what I've observed in my travels through the cubicles of various companies, that a lot of trouble could be avoided if employers invested in solid security products that prevented important company data from being unnecessarily copied -- without making it so restrictive that employees can't do their jobs.
One way to help keep information in-house is to make it possible for employees to go home and not be expected to continue their employment there. According to a Dice poll, 38% of IT professionals say they are "doing work related tasks all the time." I strongly suspect that they're trying to stay ahead in a very competitive work environment. In that kind of arena, the temptation to bring work home -- in the form of documents that probably shouldn't be moved off the main server -- can be nearly overwhelming. If workers feel encouraged to leave their work in the office, they'll leave the data in the office as well.