True and some bladders seem better than others but all will get nearly all the liquid out and the last remaining drops can be squeezed out by taking the bladder out of the box and squeezing by hand. By that stage the bladder anyway needs a clean out or if it is the same liquid to go back in, then a simple re-fill. Each bladder will do several re-fills before you have to buy a new wine box and drink the filthy stuff again to get a fresh bladder.
It's a dirty part of the whole process but someone's got to do it. Lots of sacrifices have to be made in photography
Speaking of that.
Mark Barendt, Beaverton, OR
"We do not see things the way they are. We see things the way we are." Ana´s Nin