Why?

Is it just me or does anyone else notice how often van trailers speed through construction or school zones? I can pass 10 van trailers doing 69 in a 70 I'll be doing like 72 and the instant we get to a 55 mph construction zone they'll all blast past me doing atleast 65. I know they aren't all governed either because a lot of the time they're on their phone not paying attention and when I go to pass them they want to try and race me to 80.. The thing that truly amazes me is I never see any of them get pulled over. Those LTL trucks or whatever they're called like Old Dominion or Saia those people pulling the little doubles I see them going through school zones all the time doing 5 over and I never see them get stopped lol.