So, I go to the clinic to pick up Grayson after his denutting, and the girl hands me this 'patient' form to fill out. I fill out my name, address and phone number, hand her back the form along with $40 and she hands the form back, asking me to complete it.

I had left blank the sections asking for my driver's license, email address, employer's name and address and phone number, and Social Security numbers. I told that I wouldn't be providing that info to them, and that I probably gave them too much already. Sorry.

She starts to hesitate, so I jump back in and tell her they can take the cash for services rendered, or not, but the cat was paid for, it's mine, and I'll be taking him home with me now.

They handed over the cat, like I knew they would.

Just a reminder: Too often various forms we are required to fill out for the most mundane things ask for information that they have no right to demand.
Don't give it to them.