Wait what?

Your culture doesn’t tip taxi drivers?

I constantly felt like if I didn’t tip the taxi driver, he’d drive in reverse and tell me to fuck off. Because yes they were that kind of asshole.

Because the last time I took a taxi was when I was 10 and that’s how I was raised.

They are usually self-employed

That varies wildly depending on city, county, state, and (I’m guessing) country requirements. I drove for a few years in a small-ish city, and neither me nor anyone I ran into at the usual spots were self-employed. We all worked for one of two cab companies, making hourly wages plus tip.