Obviously any sort of divisions based upon racial, sexual or religious differences are to be avoided, but having been using public transport for a while now I can see that this is an area where segregation could be beneficial.
The dividing line could be set with reference to social factors, and I'm not talking about wealth or whether or not someone went to university, but how a person functions in society, how they relate to others, and their level of social conscience.
Let's break it down:
Assume we had two bus companies operating side-by-side.
We'll call the first one 'Conscientious Travel Co' and its passengers will be ordinary pleasant people - those who sit quietly on comfy seats causing no aggravation to others, perhaps reading a book, listening to their music discreetly, or just watching the world pass by until they reach their destination and exit the bus, making sure to thank the driver.
The second company would be called something like 'Pleb-Bus'.
Their vehicles would have straw on the floor and spittoons in the corner. The passengers will be people who talk loudly on the phone, teenage mums with screaming kids hyped up on sweets and fizzy drinks, headphone addicts with their music so loud the whole bus knows exactly what they're listening to, and those who have the kind of body odour that would stop a charging rhinocerous at twenty paces.
It's quite simple - put all those who don't give a shit about others in the same place, where the only people they can annoy are those who are also very annoying. That way, the rest of us can get on with the tedium of travelling without having the lowest social denominators inflicted upon us.
Bus travel isn't exactly convenient. If you want to get where you want when you want, reliably and with minimal fuss, then bus travel is not for you.
It does however have the benefit of allowing you to get from A to B without having to deal with rush-hour traffic yourself; just switch off and let someone else have the hassle.
What you really don't want added to the misery of waiting around in the cold for a bus that's late and having to share your personal space, is the presence of people you'd generally cross the road to avoid.
This is why I'm seriously considering buying another car. While it means having to cope with driving the commute myself, it's probably easier than waiting for the gene pool to be cleaned.