There's a lot of reasons public transport isn't popular in the US. Where I live the homeless, some of whom are mentally ill, occupy the light rail trains and stations to escape the brutal cold during the winter. My friend's wife came home crying after finding a turd on a train seat. The cost is $5 for a day pass, far less than a downtown parking spot and it's not confusing at all though service is sparse
i thinks purposely designed that way, because the auto-companies have killed public transportation in the past, local govt simply never had the motivation to build out the infrastructure. the most famous is LA history.