Perhaps your right - but in my circle we simply exchange favours - I mean one friend tends to give more lifts, one has a home better suited for parties - I tend to go overboard on covering drinks/taxi costs on nights out - I much prefer a simple method of helping each other out than some fixed expected exchange.To be fair, I think how old you are comes into it as well. When I was young, we shared the cost as none of us were that well off. Now we are older, I don't really care about it and am happy to cover the costs.
As a few others have mentioned - it feels a little crass the whole thing unless its a very long trip.
Also, i'm only 28! Not that old
