The average mpy is 7k, so let's say a weekly charge is more accurate.

You can probably get away with that in most cases with on-street parking with a mix of commercial chargers and work if you're lucky.

That "probably" is the point. Your average normal car user (especially in financially challenged times) fighting for a car space on their street is not motivated to take on that higher risk at higher cost in a less competitive market to keep the equivalent of HN demographics happy.