I'm kind of making fun, but they don't want to fix the problem because those tickets are a genuine revenue stream for the city. When the revenue from parking tickets goes down, everyone panics.
See http://money.cnn.com/2015/01/06/news/economy/nypd-tickets/
I live in NYC. Parking here is so expensive that paying for a parking ticket (if you happen to get caught parking illegally) is cheaper than paying for the parking garage!
A monthly parking garage in my neighborhood (west village, manhattan) can cost $700-800. Parking on the street is not a perfect substitute, but I can get 10-12 parking tickets a month before the cost of parking illegally exceeds the cost of paying for garage space!
Parking is so expensive and hard to find (like half of the area is parking for "resident sticker only") that most people I know simply park in the residential areas and see what happens.
In the end, I finally concluded that it is legal to park across a disabled access spot in the curb unless it's in a crosswalk or otherwise prohibited.
Which is contrary to common sense, IMO... But then, that's probably why they decided to codify it.
Its not contrary to common sense - ramps are needed at crosswalks so people can cross the street. A ramp in the middle of the street, with no crosswalk around, is not needed.
Vehicles that carry wheelchairs often load and unload the wheelchair from the street in the rear of the vehicle. Ramps in the middle of the street help people in wheelchairs to enter and leave such vehicles without having to go all the way to a crosswalk.