That is all ridiculous.
I am headed out now to get me a few more of these to see if they are really all that bad. To propose a notion that what is stored in it will dry out within 6 weeks is ludicrous. I can leave a tin of tobacco open in my house for six months and it won't dry out.
This sort of jar is actually better engineered than a Mason jar, because the lid is not designed to actually be pinched down tighter by the ring on a Mason jar. This type is actually sealed by the lid.
I could see maybe if you had one and was maybe wear and tearing it by opening it and closing it, maybe with a lot of force, slamming it closed or something... But, if you just put tobacco in it and closed it, and set it aside... what do you guys propose is causing the leak? Is it flaws in the glass.
Hmmmm, what sort of test would work best? Fill it with sugar and then submerge the jar in water? Fill with water and wait for it to dry out? I feel another pipesmagazine scientific test coming on...
I've just watched the jars get bunked down with silly things like personal experience or "someone else said...", which is the most unreliable evidence there is. We need some good ol' fashioned pipesmoker science here.