Healer NPCs do damage. We have to do damage in order to pass our job quests. The game is designed in a way that we have a lot of downtime in which the only thing we can do... is damage. And yet you want to act like DPS is not part of the healer role? You might want to ignore this aspect of the role but doesn't change the fact that it's part of it.
A complete healer that actually pushes his job to the max and do their best, eventually (in a content in which they're comfortable) deal damage. Like it or not. If people don't like it, feel free to ask for a change in the gamplay and how it's designed for healers - claiming that we are not supposed to deal DPS won't change the fact that in the current game state, we are. This is not a mentality-problem, it's a game-design problem.