@jon
Just checked an ÖBB night train from Aachen to Vienna. On a mid week day (usually cheaper), mid class sleeping compartment and 4 months in advance booking = ~260€ round trip
Direct fliegt from Köln to Vienna, 1,30h, round trip = 65€

Travelling by train only something for idealists and people with principles while having enough money?

How about to turn it around? 65€ for train and 260€ for the flight… would also fit to the time saving.

@foule71 @jon two nights in a hotel in Vienna for less than 195€ isn't very easy.
@baeuchle @jon
If I’m flying early/late, I do not need a hotel at all and would sleep comfortable in my own bed.

@foule71 @jon sure, but you can't expect
1) not to pay for something that you wouldn't buy if you bought a different product
2) to have a train connection Aachen - Wien that can outperform a flight from Köln/Bonn to Wien timewise.

(I'd be genuinely interested what the actual necessary time from Aachen city to Wien City would be when flying and how early you need to get up, let alone how much the trips to/from the airport really cost)

@baeuchle @jon
I summed it up already in another reply, it would be round about 6 hours compared to 11 hour train.
I would even not argue about comfort, here train is much better. But there are many people out there who can’t afford it, so they go for flight, which makes perfectly sense to me.

@foule71 @jon Well, since most people can't sleep comfortably in their own bed, travel 6 hours AND arrive early, you're comparing apples with oranges. Day trains are faster (< 9 h) and cheaper (90 €, slower trains even < 70€ – both one way).

Your core point is valid, I know, and still holds with these prices. The comparison you use to show it is, however, invalid.