Hey Vsimone, I was doing laundry at the side of the 50s pool on Christmas night also! You're right, it was quite the place to be that night and yes, despite the cold, there were definitely people in the pool.
The washer and dryer were each $2. They did have a machine with detergent and softener, I think for $1. The only problem I encountered was that the change machine wasn't working so I walked over to the laundry area near the 60s section. Got my change there but all the machines were being used, so headed back to the 50s. All the while carrying my bag of dirty laundry.
You'll love POP, it's great fun!