> It's not a psychological trick to make things seem cheaper

Interesting! That makes sense, though Claude seems to think otherwise:

https://claude.ai/share/470906ed-6987-46b3-9e81-facfd44fc863

I feel like cash transactions are pretty rare these days at least in the US, so it would make sense for the psychological trick to persist (perhaps even more so because you don't actually have to hand over $7, you hand over a piece of plastic with your brain thinking it is $6ish)