That doesn't sound like an activist. That sounds like "sucker doing other people's work for free", which doesn't sound like an effective plan for bringing about positive change -- those people tend to "weed themselves out" over the long run.

I'm not saying you shouldn't do things to make the world a better place, like: not litter, drive courteously, etc. (Although you should be careful about which things actually accomplish a net good.) "Be the change you want in the world" (attr. Ghandi) is a good motto to keep. I'm just saying that you shouldn't expect major problems to get solved by Someone Else at no cost to you, nor complain about someone pointing out the dirty river instead of immediately cleaning it up.