I occasionally carry spray. I agree that a true encounter and one where you could respond fast enough is pretty remote. And unlike brown bears, black bears 99.9% of the time do not exhibit predatory behavior (according to the literature). But as human and bear encounters seem to be on the rise in the U.S. (with some instances of black bear predatory behavior), I would defer to individuals to take such precautions as are necessary to make them comfortable when hiking or camping. There have been instances where hikers have been attacked and killed by black bears who have stalked them (not situations where the hiker startled a mother bear with cubs). As such, I see no reason to criticize those who take steps that may be more conservative than others, particularly when it has no impact on me at all. If I were camping in an area known to have bear activity, I would carry spray. In certain parts of the country, I would arm myself as well. There is a reason why F&G carry firearms (typically slug shotgun) when responding to bear nuisance calls -- they know that while an attack is highly unlikely, it is possible. Habituated bears can be unpredictable. And I am very rational about it -- I know the risk of an encounter is very low and I know the ability to respond with spray is also very low. But there are plenty of bear encounters in the literature where spray or other defenses made the difference. Fortunately, as noted by others above, we don't have many encounters here in the northeast.