I can see why some question this. When all you've done is hunt deer your entire life you start thinking that you can hunt all big game species this way.
Bears are shy, almost 100% nocturnal, and have a low population density compared to deer and elk in most areas. This makes them next to impossible to hunt via spot and stalk.
Yes we could say too bad so sad, you can hunt them if you want but no bait. The problem is that bears eat A LOT during the summer months gearing up for winter. If they are over populated then they tend to start invading urban areas and digging through your trash. Nobody wants that so it's critical that hunters have success to manage population levels and baiting is one of a few proven mothods to take a bear.
I guess the answer to your question is you have to understand the species to understand why we hunt them the way we do.