Refuse the service to the community that one is embedded in?
I see how one can justify reviewing for certain publishers, e.g. because they publish predatory journals or their shady business practices, but refusing to review any papers would be pretty much freeloading on the scientific community. Sure that's not an option.
Although it's the publisher who ultimately creates profit from the work.
However, would reviewers be paid, then the publisher would certainly charge the authors for this. No gain.