Obviously I can’t see the bike lanes, but some common reasons for that:
They aren’t flat
There is a pothole
There is debris
The lane isn’t wide enough and the little bit of wobbles makes it safer to hug the lane
It’s not even a bike lane just a shoulder
I see all of those on my 3 mile bike commute to work some of them multiple times
Where I used to live there was bike lanes separated from the roads which was safer for cyclists, kept cyclists off the roads, and were able to be used by pedestrians as well
If you don’t like seeing cyclists in the road then encourage your community to invest in better infrastructure including things like physical barriers separating cyclists from cars