Merging Lane Police Force

I've been seeing more of these guys on the road lately. So, I was going east from Windsor, I come to a construction site on the road, so the highway narrows to one lane. But sometimes a semi truck who appoints himself as the merging lane police officer would block anyone from using the lane that's ending until it's actually ending. So they would start driving in the middle of two lanes to purposely block people from going there even thought there are like 500-600 meters remaining.

Is it legal to intentionally block people from using it until its end? Is it reportable?

I passed a semi truck that was doing it and I had to sped up because he swerved into me while I was literally still passing him -- it seems he was really upset that I used the lane until its end. I don't know why people care so much about what others do that don't affect them.



Then the other day, heavy duty truck was doing the same thing (one of those F-350 type). It was obvious, they're blocking people on purpose because he was moving back to the ending lane when he notices I was about to pass him from it.

It's like a customer blocking other customers from entering a store because it's closing in 1 hour. Whatever sickness this behaviour is, it doesn't make sense.

A quick diagram of how he was blocking two lanes. My point of view is from the car at the very top.