Never said you couldn't use the squeeze as a gravity. Just saying from using both the squeeze is a PITA to fill compared to a big zip, and the bags aren't as durable, saw one spring a leak in person on the 2nd trip out, that was enough to tell me that they just aren't up to the abuse that I put my bladders through. Its personal preference but you couldn't get me to use a squeeze filter ever again over an inline. Just creates extra steps in the filtering. I also don't wanna swap back and forth when fittings and what not. Fill up the dromedary gravity style from the big zip if I need to and move on. Again just a different approach I like the simple/fast and not having to hold and squeeze all the time to get my water out. And on the go a simple one or two dips and the bladder is full rather than trying to fill through the smaller openings of threaded caps.
And I may end up with a big zip eventually but won't need it this year with a good water supply close to camp and I may find I dislike filling the dromedary but no way will it be as bad as using the squeeze bags, I agree they suck and freeze your hand when trying to fill a 10L camp bag. No more squeezing for me.