Under my personal heatmap, I found activities logged in other states I have never been.. wth?

I just moved to a new city and decided to open up heatmaps to look for local routes. While I was under my own personal heatmap, I noticed something very strange... 2 activities were recorded in places I have NEVER been, one in Sanfran CA and the other in Seattle WA. They are not just straight lines indicating a GPS error either, and I live in MI anyway, closest I've been to either of those places is Utah and Nevada. When I zoom in on the activity, they are not just in random places either, they both appear to correlate directly over a building. What is going on here exactly? If they had been straight lines in completely random places I'd chalk it up to GPS errors, but Seattle and San Francisco? Two places a lot of scam calls and junk mail comes out of?