Years ago I had a client spend around $100 and pay with cash. They then realized they needed one thing additional, which was $7. They were out of cash at that point, so they wrote a check.
The check for $7 bounced. After they made no effort to pay, I sent them to collections for the seven bucks. A year later they were buying a house, and the ding on their credit caused them problems. I know this because they called, screaming, to let me know.
$25 to park in NYC?
Wouldn’t that be like the best deal in the world? 
(All I know about NYC, I learned from watching Law & Order)
I got one this summer in Nashville and ignored it. Nothing happened. Credit is fine.
An old joke:
Before going to Europe on business, a man drove his Rolls-Royce to a downtown NY City bank and went in to ask for an immediate loan of $5,000. The loan officer, taken aback, requested collateral. “Well, then, here are the keys to my Rolls-Royce,” the man said. The loan officer promptly had the car driven into the bank’s underground parking for safe keeping, and gave him $5,000.
Two weeks later, the man walked through the bank’s doors, and asked to settle up his loan and get his car back. “That will be $5,000 in principal, and $15.40 in interest,” the loan officer said.
The man wrote out a check and started to walk away.
“Wait sir,” the loan officer said, “while you were gone, I found out you are a millionaire. Why in the world would you need to borrow $5,000?”
The man smiled. “Where else could I park my Rolls-Royce in Manhattan for two weeks and pay only $15.40?”
Somehow I’m getting the impression that you enjoyed that phone call waaay too much. 
yes an agency will collect on 25 dollars and add charges where 25 can go to 50 or more easily … because calif lets them charge “reasonable” expense fees …
More than you imagine. I laughed at their predicament and offered zero help (I couldn’t even recall the name of the collection agency I was using at that time).
This link contains the following sentence
“for additional enforcement we can supply booting and towing technology for use on vehicles associated with unpaid parking tickets”.
So you might want to pay that bill.