If I or my opponent lands on our own frog, we lose 5 points and the opponent gets 5.  That's a 10 point advantage to the opponent.  If that happens on the first move, I do a shoot move, hit my own frog, and am in the minus the equivalent of 10 points.  Then if my opponent only finds three of his/her frogs, they'll have 20 points.  I now need to find 5 frogs before my opponent finds just 4.  It's a huge disadvantage.  Wouldn't it be better to keep the odds more even by just giving a -5 and nothing to the opponent?