This is the epitome of the issue I'm talking about -- you people seem to presume the engagement ends at the simple step. For some, it will, but those people weren't likely to engage larger in the first place and reducing the consumer waste doesn't hurt.
For others, it will make them aware of the larger call to action, to get them to join advocacy groups that punish industrial and systemic issues.
I can't stop fascism or climate change or pollution on my own. I need MORE people engaged and telling people we need all or nothing solutions can only lower the number of people willing to take action. Individual, even trivial steps matter.
Look at the people telling you to give up.