Some of the things I found surprising (compared to other SE asian countries)

Cash is much more ubiquitous than credit cards - I couldn't charge suica cards/ etc. Lots of places you are used to using cc in the US only use cash

ATM's only work during some hours (?at the bank) unlike 24 hour ones in the US and also there seems to be a differing charge depending on what hours you use them inside 7/11 type stores (which are available more hours) if I remember correctly - maybe someone with more knowledge could comment?

Also found some great sushi and other food in a local supermarket in Yokohama AND everywhere fresh foods are checked every few hours and MARKED DOWN, got some incredible sashmi this way that even tho marked down was better than most I had in the US.

There was a senior discount (foreigners eligible) that wasn't obvious, but quickly granted when I asked for the bus to Haneda (or was it Narita) - sorry can't remember. Anyway a nice surprise and don't know (maybe someone could say) if there are other senior discounts for transport.