While it is possible, I would suspect something else. Water (tap) is incredibly reliable unless you live near Flint MI.
It is easy to miss a step (or get a bit lazy) on the cleaning side. Note that sanitation won't properly sanitize something that is even lightly dirty. PBW or OneStep for cleaning, a good rinse, and a solid sanitation step with StarSan, SaniClean, or Iodophor should be adequate for most mead makers. I do occasionally go for a very long and hot carboy soak with PBW when I notice scum or "spots" sticking.
I follow tailored SNA protocols that include pitching a fairly large amount of yeast (4-5g to a gallon for a 1.150 gravity), along with rehydration with goFerm at 1.25x the weight of the yeast I am using. This, along with sulfite conditioning of the must before pitching (when using any fruit), seems to give the sacc adequate opportunity to get up and fermenting and outcompete any or most of the residual bugs from fruit and honey.