My point is not whatever a dragon or a dog will be able to commit a bite attack. Instead of comparing a dragons and a dogs bite one could compare a giant and a character and a goblin and a character trying to push a rock at each other. If the strength of the character is the only value that matters then the character will have the same probability to win against the goblin as the character will have to win against a giant. My point is that the size/skill of the NPC/monster doesn't matter.
If you want the STR of the monster/animal to matter that is the purpose of an opposed roll, but as discussed some are requesting more guidance/stats to support opposed rolls for that very reason. A dog would have a STR or BODY of 10 and a Dragon would have a STR/Body of 16.
The implied use of bane/boon, though, is suggesting a wider "range" of use than some GMs are used to for a straight up roll. It seems that in a bite/constrict of Large monsters inflict a bane on a straight STR roll. A mundane dog would be just a straight STR roll and a cat would be a STR with a boon. That is three category of uses and perhaps some GMs want a more granular set of choices.
As an example, what about straight STR check against the bite of a tiger or a bear? A GM might think they need a penalty or bonus that is more granular between the grapple bite of a dragon (monster level challenge) and grapple bite of a (minion level NPC challenge) dog. Perhaps flat bonus like a +1 or +2? (A boon/bane is a fuzzy +5 bonus).
Or some "animals" could become mimi-monsters much like the Vampire Bat swarm to demonstrate the range of bane and boon.
I am not against more granular bonuses but I think this example helps illustrate the point better.