A bus will pretty much always be inferior to a car. Mathematically impossible to run on time. It never gets you where you want to go, just kinda close usually. If one doesn't show up, there is no real feedback without an extensive background metadata system. Never as clean as your own car (unless you're one of those carbage-loving people I suppose, but then you're just going to litter on the bus anyways). Obnoxious, loud, smelly, or crazy people you have to deal with.
I'll never understand the crowd so desperate to have them, but I'll still support the cause if it cleans up the highways for me I guess.