My practice & experience is identical to Old Salt's.

(Egads!  Surely that's reason enough to cause me to rethink things! ;D)

Seriously, though, ArneS makes a valid point about putting your trip at risk.  I would never advocate for someone to follow my practice.  Possibly I'm just lazy but, for whatever reason, it has been risk I've been willing to take (filling my water bladder in larger, deeper bodies of water, in lightly travelled areas, a few hundred feet from the shoreline).

Another explanation: perhaps our (alleged) minds (OS's & mine) have been subtly & irreversibly altered/transformed by all that Canadian Shield water we've consumed over the years.  And everyone knows, as "Quetico Zombies", we must drink more....

Jimbo  8-)