I’m generally not a lefty type person, but aren’t resource agnostic fines actually less blind-justice than the alternative?

The wealthy speeder shrugs it off, while the poor speeder has to change their spending allocation in a way that is noticeable and could be challenging.

Why should the punishment have a different impact based on wealth? The felt impact of a monetary fine fundamentally depends on how much money the offender has. Whereas the classic “locked in a cage” punishment affects everyone equally.