I don't remember if it was Japan or Taiwan we were in where they had little baskets that you exchanged money through for sales to avoid spreading germs from hand to hand contact (this was in 2008)
The handing the card directly to you thing I could see as just being polite.
Yea, I think I would give a small side eye to someone who slid the card back at me across the counter.
At the childcare I worked at there was a locked box on the wall that all the $ had to go in. If it was a check the parent had to put it in. If the parent paid cash you had to give a receipt and they had to watch you put it in the box.
I could see teachers doing that if they want to protect themselves. If they don't touch the money, nobody can accuse them of stealing. Some teachers make students deposit the money into a box and then they have another teacher watch/verify everything that came out of the box. It helps prevent the "You lost Suzy's $100 bill!!" or "You changed the amount on my check!!!!"