Answer:
free rider
Explanation:
A free rider may be defined as a person who benefits or gains from the things without expending an effort or without paying for it. In other words, a free riders are people who utilizes goods or take advantages of others without paying for their use.
In the context, when I breathe the air which is cleaned by some other interest group to which I do not contribute or do not belong, I am an example of free rider.