[ggreer]

It looks like it's not a fine in the sense that refusal to pay can result in suspension of your driving license and possible wage garnishment. They don't even call it a fine but a "penalty". Basically they ask you for $50 or $100 depending on which limit you exceed, and refusal to pay risks a court case. I'm guessing the bridge needs to be inspected after the weight limit is exceeded or if a taller vehicle strikes the structure. The cost of inspection likely exceeds the penalty. They could easily ask for thousands of dollars in compensation. And even if you win the case, you have to pay for a lawyer and spend time in court. It's easier for both parties if the driver just pays the penalty.