The work around solution is to cut a straight, smaller tree to use as a support post for the roof hub. Just wedge it in solid between the center roof hub and the ground. I've left some blinds out all winter in WI, IL & MO using that method and haven't had one outfitted with a support (remove when hunting and prop back in place when done) that's snapped rods on me yet, but I rarely have one survive a good snow fall that isn't supported...I typically start using the supports in mid Nov on through when the blind is pulled.
P.S. Cut the support a couple inches longer than you think it has to be. You can always angle it a little and need that pressure for it to work. also, it REALLY stinks when you cut it even a 1/2 inch short and have to start over.