The costumer doesn't want them because the service constantly fails and they don't want the customer because he constantly complains. What's abusive about that?

The costumer doesn't want them because the service constantly fails and they don't want the customer because he constantly complains. What's abusive about that? A perfectly healthy non-relation. The only abusive thing would be gov. getting in the way of it and forcing them to accept the customers or the costumers to accept the ISP.