Truth is, they probably don't know those things.
What they think they know about bears came from television or movies, where animals are almost always the heroes and humans are almost always the villains. They believe animals are capable of human-like thoughts and emotions.
And they believe the world would be a better place if humans would simply leave animals alone. No hunting. No livestock. No pets.
It doesn't seem to occur to them that we live in a world inhabited by 6 billion people. Humans' presence has altered the landscape - altered the balance of nature - in ways too numerous to count.
If animals were left completely alone, there would be unintended consequences.
Within a few generations, most of the animals' fear of humans would disappear. Herbivores would come to view humans' farms and gardens - remember, humans wouldn't be eating meat anymore - as easy food sources. Large carnivores such as bears, wolves and mountain lions would come to view weak, slow-footed humans as prey.
In other words, the same conditions that spurred humans to exert dominance over animals would have recurred. Humans - the smart ones, at least - wouldn't allow themselves to starve simply to feed Bambi, or allow themselves to be torn apart to feed Yogi.
They'd start killing animals again.
And chances are they'd start eating the animals they killed. After that, they'd start hunting and domesticating animals for livestock and pets.
The late, great newspaperman L.T. Anderson had a term for the Tahoe activists and others like them - "the Terribly Concerned."
Only in the minds of the Terribly Concerned is the welfare of cabin-raiding bears more important than the welfare of the people whose cabins are being raided. It's a mentality I simply cannot fathom.