“they sit on the ladies side before all the ladies even are all on,”
This is not unique to a bus. The Rav of my shul was very adamant that men not sit in the ezras nashim during the week when ladies are not in shul, yet there are those who persisted in theis behavior. It got to the point where the Rav instructed the shammas not to turn on the lights or the heat in the ezras nashim to “encourage” all the men to sit on the “mens side”. There are still men who go straight to the ezras nashim, and daven in the dark and the cold. I guess they just dont like being in shul. At least they “chap a minyan” on the bus.