The problem with privaitised bus (and rail) companies is that they charge according to the cost of providing the service, because they are unable to take account of the benefits to society as they could do if they were nationalised.
When someone uses the bus, it benefits all of us because they're not causing any extra pollution or traffic, which makes the air better for everyone else, and the roads clearer for everyone else. It also makes parking easier for those who do still drive. Because we all benefit, we should all pay, by subsidising the fares.
I lived in the Czech Republic for a while, and public transport, as in a lot of Central Europe, is very cheap indeed, and very regular - you'd be an idiot not to use the frequent, cheap and reliable public transport for most of your journeys - that's what we need to get people using public transport. I'd gladly forsake wi-fi on my bus (that was quite the thing for a while it seemed) in exchange for not having to wait half an hour for it and pay more than it would cost to drive myself for the privilege of trying to shift some crumpled copies of The Metro so I can sit down whilst the driver pretends he's Stirling Moss.