>Imagine how expensive shipping would've become overnight if all these trucks had to pay their fair share and passed the costs to their customers.

The roads are already being paid for and maintained at their current state. All you'd be doing is making goods slightly more expensive and other taxes slightly less. About 1-4% of your total tax burden goes to the roads. That's a small enough total number to be easily buried among your annual spend on goods.

Like if roads were these huge financial burdens that didn't amortize away to practically nothing.