I wouldn't dream of asking a friend to contribute to my flying these day's but of course I can afford it now but when I remember back to being a student, we would alway's split the petrol in the car even if we were only going 30 miles.
I suppose it boils down to the hobby v proffessional thing, if you want to hour build for your atpl, you are usually the poor student and I think we should contribute to your costs, if you want to fly as a hobby, you should be able to afford pay for it or do something else.