For about 20 years, I hosted foreign exchange students in the US and did volunteer work for exchange organizations. That led to doing a lot of senior portraits. The trading of senior "wallet" photos was a US only tradition, so exchange students had to have the tradition explained to them. Most loved it and thought it was cool.
My last exchange student was 14 years ago, and then I "aged out" of the system. But this year I did a senior portrait session for the son of a friend. When we talked about wallet prints, I was told they don't do that any more. I checked around, and it's apparently true. At least in my area. The tradition has died. I suppose that, since the kids have thousands of selfies on their phones, they don't see the need for wallet prints.