It does seem to be hit and miss as to whether you'll find a usable hose or not. My system is usually give it a rinse if it's there and nobody's waiting and not if the hoses aren't compatible or somebody is waiting. Seems to keep the tank in reasonably good shape for us.
That said I do like the idea of bringing a spare male hose end and a hose clamp to up the odds a bit that you'll be able to do a rinse.
2007 Shamrock F19 hybrid - 2010 (22 nights), 2011 (24 nights), 2012 (11 nights)
2013 Surveyor Select 235RKS - 2012 (6 nights), 2013 (32 nights), 2014 (26 nights), 2015 (37 nights), 2016 (14 nights)