My point was that you don't need support for when it works, you need support for when it doesn't.

That's fair enough. I just don't acknowledge their right to tell me what I can or cannot trade once I've paid for it. It comes down to a question of what I've paid for: have I paid for transportation from A to D, or have I paid for three stations worth of travel with an entrance and exit? The transit company would like to define it one way and perhaps we'd like to define it another. But there's no cheating.

Life may correct you one day. I had the Nexus 4 (supposedly the ideal CyanogenMod phone), and many serious things didn't work. Power button broke, USB charging developed some problem, one or two apps wouldn't sync on CyanogenMod (working perfectly on stock), and 3G didn't work acceptably (extreme latency). It was bad enough that I'm never buying another unsupported phone.

That's true, but it doesn't account for the facts. For example, going 6 stops and 7 stops frequently costs the same (in my city). Furthermore, the fact that the subway would like to charge me for whole tickets and not fractional ones doesn't mean I'm going to cooperate. When a company tells you their product cannot be transferred, or that its legal value is zero, do you always listen to that?

Here's a more palatable variation, if you can accept these premises:
- a "fraction of a ticket" is a valid asset for the purposes of trading
- my ticket from A->B->C contains a "B->C" fraction if I've ridden one stop and am currently at B

Motivation:
- Short subway trips are overpriced due to minimum prices
- Trips of 2 or more stops are fairly priced
- You want to travel 3 stops, A -> B -> C -> D
- I want to travel 1 stop, B -> C

Default procedure:
- You buy a ABCD ticket (standard price per distance)
- I buy a BC ticket (ripoff)
- We have paid for a total of 4 stops, or distance=AB+BC*2+CD
- We have paid about standard_rate*3 + ripoff_rate*1

Arbitrage procedure:
- You buy a ABC ticket
- I buy a BCD ticket
- We trade at station B or C
- We have STILL paid for a total of 4 stops, or distance=AB+BC*2+CD
- We have paid about standard_rate*4 and saved money WITHOUT traveling for more than we paid for.