How come trucks always pull to the right, but cars don't?

Mind you, I understand why trucks pull to the right. We're driving the right lane, and the highway is tilted to the right so the water will flow off, etc

But somehow regular car with decent alignment manages to drive dead straight in the right lane, while every single semi truck I've ever driven always wants to go in the ditch.

Is it just a center of gravity thing? Or is it because cars have more complicated independent suspensions that are designed to keep them going straight on a slant?

Or maybe trucks are supposed to go straight, and all the ones I've driven just have bad alignment in the same direction, idk...

 

Then how come it never pulls to the left?

I've driven tens of trucks and pulled hundreds of trailers and I've never had a truck that wants to go into the left lane on a windless day

 

Honestly I haven't bobtailed on the interstates for such a long time. From what I remember, they're just kind of all over the place

 

Mine probably wouldn't pull to the right on a truly Flat Road either... but interstates are never truly flat. That's my whole point, on the Interstate truck always wants to go right.

It also varies by state. Places that get a lot of strong rain make their Highway a little bit more slanty, I think