On our Nova cruise we were told by the HD that they do not stock Pellegrino, Perrier, etc. for environmental reasons. I said I thought that should be made clear, in advance, to long time cruisers who expect it. He repeated the policy. However, the next day our butler told us she had "permission" to give us Pellegrino in the room. She kept our fridge stocked for the rest of the cruise, in part by "hiding" extra bottles in our bar cabinet.
When we asked for Pellegrino in the dining rooms or bars we were told the house made sparkling water was the only option.
Hopefully, on our upcoming Muse cruise Pellegrino will be available.