There's a difference between valiantly trying to defend its families despite the obvious odds (and hell no, it's not being too dumb to live) and being dumb thinking it can seriously beat a human. Even while whining about how things turn out as they did and fearing the human, some born shitheads try to act great. Leading to amusing consequences. This one shows the difference well.
It also shows the hypocresy of how Yukkuris can wrong other living beings but if a living being dares to attack them for that wrong, the yukkuris get "Rightfully offended" and decide to "right the wrongs" of the being attacked "daring to oppose them and not letting them ahve their way".
That for me, made the whole umbrella stabbing more delicious. Of course, i'm still waiting for another comic like Infinite Bean Paste to show up, on which the anons regardless if the yukkuris understand or not, counter each of their retarded arguments and logic making the yukkuris, at least, realize that no matter what they say, the anon will counter it and not "awknowledge" their logic.