(phat -- this isn't directed to you. It is a response to the OP)

There are bunches of studies and reports that repeatedly draw the same conclusion; bear spray is effective.

None the less, such studies don't convince everyone (see above) and, to a point, that's OK. Afterall, it's their health and safety that is in play. In a sense, it's similar to wearing seatbelts, motorcycle helmets, life preservers, etc.

But most who discuss the efficacy of bear spray are also interested in, and appreciate, the areas and wildlife where bear spray is applicable. With that in mind, consider:

Bear spray not only gives you some protection (believe it or not), it also protects the bear. A bear that breaks off an encounter and leaves the hiker unharmed is quite likely a bear that will live another day. A bear that swipes/mauls/kills a hiker is a bear that, at the very least, will be removed. More likely, it will be 'euthanized.' Bear spray can prevent encounters from becoming violent and reduce/prevent injuries.

Carry the bear spray...you might save a bear's life as well as your own.

FB

p.s. IMO, if you don't want to carry bear spray you shouldn't put the bear(s)at risk for the sake of mere recreation. In other words, don't hike in grizzly country. There's less than 1200 of them in the Lower 48 and they take up very, very little space (Grand Tetons to the Canadian border, and a handful along the Idaho-Montana border). I know it's a compromise...our activities already do enough to put the bear at risk. But bear spray is one way of mitigating those activities. IMO.