Remember, that is exactly what an exploiter will say to you. They'll always try to place the blame on the individual for the damage they're doing collectively. Same with the BP Oil campaign when they invented the "carbon footprint of the individual" while being one of the worst polluters in the world.
If you look at real, concrete, systemic changes in the world, the times where it has happened because of "optimism" is close to zero.
Remember that the exploiters will always demand that people use the proper channels, because they own those channels, and can make sure nothing ever gets through.
There are only two ways to deal with exploiters. You can try and use your voice a few times, and if that doesn't work, you start using your hands.