When you are young, you think you can influence a lot of things, but when you grow older, you realize you can only really influence a few of them.
Knowing what is worth trying to change and what not is the key to be effective. You can’t just waste your time in trying to make the post office better if you are not willing to sacrifice your time and attention and create focus groups and reach the higher management.
As well as you can’t have a successful nonprofit organization without the sacrifice of few years to raise awareness about the problem you are trying to solve.
Just accept that your time is limited and instead of fighting windmills, focus on a small part of the trouble and fix it.