anti-ism-ism is the one true-ism!
The drawback of this approach is that it is almost impossible to predict when you have found enough materials to finish it. But it's cheap and fun, and as long the rabbits are OK waiting for their new burrow, there's no reason to plan ahead too far. ;)
Indeed... and there is some time pressure, it has to be finished before temperatures drop too far below zero.Luckily there's enough material around!