Well, we now know, courtesy of Harry's latest court case, just how far the press were targeting the royal girlfriends of the day. If they were putting trackers on cars used by Chelsey, I bet they were doing just as much to Kate. It must have been relentless.
Chelsey was outside UK for much of her time with Harry, and the time she was here she was at university. She didn't have a job here until after the relationship had ended.
So we don't really know what lengths the press would go to to infiltrate the girlfriends' working lives - if either of them had worked, would the press have planted people in their workplaces? Would there have been attempts at stings? Would they have been able to have had anything like a normal working life?
We don't know why Kate left her first job (nor whether intrusion played a role). We do know that she then went to work at a place where the workforce could be trusted (possibly even vetted). And no-one knows whether she was working just as diligently as the other employees (often assumed she couldn't have been)