Return train fares VS singles?

Question

How do the train companies justify charging around the same prices for a single and return ticket - £46.50 or £49 respectively in my case (Plymouth to Portsmouth)? Has it anything to do with the near monopoly they have on the tracks, despite gov't incentives for competiveness?

And while I'm on the topic, why is it so expensive relative to driving? For example, one person to drive from Plymouth to Portsmouth (150 miles) it's around £25 in petrol. Four people in one car = 6.50 each. A train can fit 100 or so, each paying around £40 or so each for a similar journey. What are their overheads, or are we just being exploited?!

PS. I appreciate if we're to look at cars, you have to include insurance, wear, initial cost etc. but imagine they would still be greatly cheaper in the long run!

As an afterthought, is there anything that can be done to reduce these prices in the near future? It certainly doesn't encourage anyone to stop using their cars unless they have too!

Thanks...

Answer 1

Most people want to get back to where they started, so they have to offer a (fairly) reasonable rate to get people to do the journey.

Trains, especially new ones, are not cheap to buy or lease. Staff and signalling costs. Fuel consumption for diesel multiple units varies depending on the number of stops involved in the journey and the age of the train (newer trains generally use more fuel because they're heavier as they're more crash-worthy), but is usually in the range 0.6 - 1.2 kilograms per kilometre - assume for simplicity that diesel weighs 1kg/litre, like water does, so for a 150 mile/240 km journey we're talking up to around £260 just for fuel, and it costs the same regardless whether the train's packed or just has a handful of people on it.