Actually, the journal should handle a problem like this much earlier. It may be that the "reviewer" just doesn't know how the game is played and that reviewing is seen as a contribution to one's peers. To be a professional is to offer this service and, by cooperating, others will, hopefully, do the same.
Therefore, send a letter to the person when they first refuse for this reason, explaining the process and the fact that reviewers are never paid and that paying them would increase the costs to readers as well, given that there are more reviews done than articles published.
At that time, let them know that, while it is possible to refuse any given paper for review, if they refuse to participate in the process at all, then their future work won't be accepted as a matter of policy.
I have refused to review papers for a variety of reasons, often because I felt I didn't know enough of the subject to do it justice. No one should have to make reviewing their first priority. But if they refuse to participate in a society as constituted they won't be welcome in it.
They are, of course, welcome to work for a more rational system if they like.