Are you going to be in trouble if you don't contribute?
Does your outfit give a ham or turkey to staff? Or a gift card
to the grocery store? As a staff nurse, long before there were any except currently grandfathered NP's, staff received a turkey at TG and a $25 grocery store gift card. At Christmas, it was a ham and another grocery store gift card. These were from our hospital employer. Back when $25 was a nice sum.
Doctors bought a box of candy, which none of us needed, stuck it at the Nurses' Station, and that was it. except a couple of docs bought a box for each shift. But they never gave money or a party that I was aware of.
Hospital gave staff a nice meal on TG and Christmas, except that Night shift got a bag lunch. It was a nicer than usual Night meal. One place gave a breakfast for Night staff - after the shift ended.
On Christmas, you could have your family (spouse at least, don't remember if kids were welcome) eat with you in the cafeteria on Days or Evenings. If you got a meal break.
$500 sounds like a lot for an NP to give, but I know my head is back in ancient times with regard to money and what it will buy these days. Perhaps it is a proper amount. But if you don't really have it, you don't have it. Give what you are able, I guess.