I have to admit that I tend to go back and forth on this issue because I think there are strong cases on both the pro and the con for allowing the perfect game, but currently I'm leaning away from it---not out of an 'everyone should get to play' viewpoint (although that point becomes especially meaningful in a best-of-one scenario), but rather because I think it narrows what the game of Kubb is.
In its most reduced form, Kubb is a race to clear the baseline then topple the King, and if you use this as your guiding star then you should be in favor of allowing the perfect game. In practice however, Kubb becomes an amalgamation of several discreet 'mini games' - Who can be the most accurate with batons (at any distance); who can throw the best groups, who can stand their opponent's field kubbs in the most strategically defensive way, who can be more consistent (and efficient) at clearing the field, etc. Being the better player or team at 8 meters is a big part of the game, but to me it's ONLY part of the game, and I'm resistant to allowing the rest of the game to be glossed over.
In the game above, The Ringers answered our 5-for-5 open by clearing the field with 3 batons then going 2-for-3 on the baseline to put 7 kubbs in our hands to start the second round. That was AMAZING play, and it put the pressure back on us to seal the game. We struggled a bit with it, and if the group wasn't quite as good or if we'd have had one more miss then The Ringers would have been alive to fight another round. It was a short game of Kubb, but it was COMPLETE. Both teams had to show their mettle in every phase, and the team that played better enough, in enough phases, was the winner.
Sukface might feel differently since they were on the other side of the issue, but I've been in their shoes before as well. In a recent ladder tournament match with Dobbie I opened 5-for-5. Dobbie cleared and got a base, and in round two I failed to clear the 6 in play, which Dobbie promptly turned into a win. At the time I didn't think (and even looking back on it now still don't think) "Damn, I wish I'd have had the chance to kill the King turn one", but rather I think "Damn, I wish I would have handled my business in the field round two."