The reason why I have a hunch it could be a fluke is:

1. For Zenefits, the WorkBC job postings (https://www.workbc.ca/Job-Seekers/Employer-Profile/117670/Zenefits-Development,-Inc.aspx) mention the job type as "temporary". It's the company's first office outside of SF so there's a chance the its primary purpose is a L-1 visa holding tank.

2. Tableau's co-founder Chris Stolte is a Vancouver native and an SFU computing science graduate. Maybe he was just homesick.

Further complicating things is the news that Hired.com's Canadian arm (Hired.ca), which went live yesterday, will soon roll out in Vancouver as well (source: http://betakit.com/hired-launches-in-canada-as-talent-crunch-grows/). I can't see how that's not promising, although it's possible that the emphasis is on poaching Vancouver talent for Seattle jobs.

What do you think?