Currently pregnant. We can do all our regular travel by walking, cycling or public transport. At a pinch, could pre-book a taxi with car seats.
I'm loath to spend money on car seats only for them to see occasional use. Also, given we don't have a car to store them in, it's more space taken up in our flat. I think I'd rather avoid the journeys that need travel by private car, at least until the kids are older.
Parents who don't have a car: did you survive without car seats, or did you find you needed them for occasional use? (I'm aware of the regulations around requirements for car seats, hence why I'd rather just avoid private car travel).