I agree that one should not deceive their employer. At the same time, if their employer does not notice a drop in productivity/performance from the employee, what's that say about that company's ability to actually measure employee performance?

I think a lot of companies have poor project management & employee performance measurements, so half the time, people only have half the picture or don't know what the heck people are supposed to be doing and if that's actually getting done. That only becomes more complicated when projects are abandoned and/or requirements shift every quarter.

So people like the guy with two jobs should be fired if management was better. And more employee surveillance is needed to help managers do their jobs better. The other option is integrity and trust.

I agree on the latter, measure deliverables & people's contributions to the deliverables. Having paranoia that someone is working two jobs, so you need people in office or you need to install aggressive spyware is extreme.