Issuing speeding and relatively minor traffic infringement fines is justified on the basis of safety. Speeding fines provide a disincentive to endanger other people, so we improve road safety. In fact there is a far more efficient means to ensure road safety.
We don't want people to speed because of the danger of hurting people. If this is the case, then why not just make people pay when they hurt someone? If you kill someone (accidentally), then you have to pay compensation to their families. In practice of course the money would be paid for by insurance companies. Someone pays the insurance company their premium, and if their hurt someone accidentally, then the insurance company pays up.
All you have to do is to make information about speeders available to the insurance companies. If someone has been caught speeding, then the insurance company will find out, and increase their premiums accordingly. Speeding by greater amounts are an indication of increased risk to the insurance company, and will attract a higher increase in the premium.
The same could apply to all minor traffic violations.
Of course this will not happen, because the government would not make money from it.
The system of fines has little to do with safety and a great deal to do with raising revenue for the big pork barrel. The taxpayer pays millions of dollars for television campaigns about speeding so the government can justify raising many more millions of dollars in revenue from fines. And they justify this by humanitarian 'people before profit' slogans.
It's pretty poor.