No, it makes it so that the outcome is more equally felt across all income levels.
What does someone affluent care if they have to pay a $100 speeding ticket or a $20 parking ticket? That's just the cost of business for them.
Because you want to... hard stop behavior. Parking violations cause harm, so the fine should be a function of damage to society, not some weird fetish to make people feel pain.
If behavior is so unacceptable that you want to prevent it altogether, criminalize it.