The wells in Masouri (which are now running with fresh drinking water again) have recently been supplemented by little kiosks provided by the municipality to supply free refrigerated water. This is a thoughtful addition to the sometimes-unreliable water supply.
I noticed tonight that occupants of one of the campervans currently parked up within Masouri had driven to the middle of the village to do their washing-up using water from one of the little kiosks.
In a place like Kalymnos, which relies heavily of visitors staying in (pretty cheap) apartments, you might assume that campervans would keep a low profile.
Wild camping is part of climbing culture and in Kalymnos appears to be tolerated if done with tact and respect.
By all means use the free wells to top up your water but please don’t do your washing-up in the middle of the street and in front of the restaurants and apartments!