Cushioned seats on the tube - why?

One thing that I was wondering about in London: why in the world are the seats on the tube cushioned? They get dirty so much quicker than if they’d be plastic, or whatever is best suited. I don’t remember what they were in Paris, but I don’t think I have seen cushioned seats on a subway before.

I’m quite glad they are cushioned, sure they get nice and scummy with dead human skin, and much worse. But it’d hurt your arse if they were plastic!

Especially on the Northern (Misery) Line, you can be stuck on there for hours!

How about clothless cushioning? Seats can be soft without fabric on top.

I mailed the Tube’s Customer Services department, and the reply I got confirmed that the reason is to give extra comform over longer journeys. For what it’s worth, I live on the eastern edge of London and have friends in the west. Journeys I make to visit them have taken more than two hours (nothing to do with delays or problems en route), and I wouldn’t have wanted to sit on a hard, plastic seat all that way.

The reply also said:
“With regard to the particular materials used: this is dictated primarily by safety concerns. All our trains have to meet stringent standards set by the Health & Safety Executive and Her Majesty’s Railway Inspectorate. All materials must be fire retardant which limits the types of material used.”

Alright, that explains it somewhat. They probably do clean them thoroughly from time to time. But all those butts leave a mark.