driving etiquette is different.

I figured this would be the key issue. Even in the US, people drive very differently in different states. I lived in south Florida for a while and although I could go on about drivers there, what really makes it tricky is the design of the roads/lights. There are some on-ramps where you'd have to cross a solid line in order to get onto the main highway (and if you don't, you head straight into an off-ramp.) This is a distinct problem around Miami on I-95. There are also left-turn lights that don't activate at all during rush hour (despite having left-turn lanes.) This also occurs in Miami, specifically on US-1.

Both of these situations mean having to technically make illegal moves in order to get where you need to go, by either crossing a solid line or turning left on red, respectively. It's absolutely maddening, and makes being a law-abiding driver effectively impossible.

I don't envy anyone trying to drive in roads like that, let alone people used to driving laws in another country who may be unfamiliar with how to safely navigate such situations.