Yes, those are both valid solutions.

However, in some cities public transit isn't very good, there aren't enough lines to actually get you where you need to go consistently. Outside of cities, public transit is mostly non-existent, so you need something else. Taxis can work, but they're also expensive and you have to rely on others, which can also be anxiety inducing. What if my taxi doesn't show up, or shows up late? What if the taxi driver makes me feel unsafe? I expect some people would like to be more in control of the situation, just without having to actually drive.

Hey, these things may not apply to you, and that's fine, I'm glad there are simpler solutions for most people. But having used public transit every day for many years, I can honestly say that while it is usually the cheapest and most efficient solution, I can still understand why people might want something else.