As has already been mentioned, these issues have money at the heart of them and work or career is something which is done in return for money. Therefore there will always sooner or later be a conflict of interest if you make it your work to solve these problems.
Originally Posted by NewbGTD
But, yes, it's difficult to see what one person can do to make a difference. And even if they do do something as, again, has already been mentioned, it can make the situation worse despite good intentions (re:banning water bottles).
The answer may be not so much to focus directly on the desired outcomes but to develop a life philosophy which is congruent with the higher level desires. i.e. live with less focus on financial gain, competitiveness with others. Perhaps by living this way others will observe the benefits of a more wholesome life with less reliance on energy and money intensive things and the avoidance of conflict and decide to adjust their own philosophies accordingly.
Then again, there are always people that are driven by greed and conflict for the sake of itself. But these people must also be dealt with in your everyday life. So if you can develop your philosophy to deal effectively with these people, without disrupting your life you may find a solution that can be scaled up to solve the bigger problems of the world. After all, all these problems are caused by people.
You fulfil your 50,000ft purpose by achieving your lower level goals. Fixing your bike may not prevent environmental catastrophe but if a lot of other people notice how much money you save cycling rather than driving then they might think about doing the same. It's almost like not trying. The worst that can happen is you live your life the way you wanted to.