You can say that easily but, for people whose lives and those of others depend on such products, they don't have the luxury of going to a store or mail-ordering them in middle of their tasks.
Do you really think that a cop will have the time to walk into a shop in middle of a pursuit, when the suspect may be armed and present danger to anyone nearby?
Do you really think that a medic will be able to leave the patient to find another light, when the patient is laying there bleeding and unconscious?
Do you really think that a firefighter can simply exit out of a burning building when his light dies, when there are people trapped inside who need to be rescued?
Do you really think that a soldier has the time to find a replacement light in middle of a firefight, when the lives of not only him but his comrades as well are at stake?
And we as a community are none of these people, although there definitely are some of them amongst us (thank you for your service!). For people like this, I can easily see why it would be worth the price for additional assurance that the tool you need will work how you intend it to when the time comes for its use. If I was a soldier, you know I'd be buying a SF. BUT I'd also have other lights handy. The CPF community consists mostly of hobby enthusiasts. I held my first surefire the other day, and while I was impressed at the quality of it in my hand, I held other brands' lights that felt just as nice, and cost 1/3rd of the price for way more output, modes, and control.
I say this not because I have anything at all against surefire. Anyone who wants to buy one, feel free. I absolutely wouldn't mind having one myself. I just don't feel at this time that the light justifies its price for me, given the features and output it provides. If things start to screw up, then I might, but none of the reputable brand lights I've bought have had any issues at all so far.
I don't use any of them mounted on weapons (but i do use them wet often). I do mount a few on my bike and ride aggressive MTB. no problems so far after dozens of hours riding.
For me personally I do not see a reason to buy SF, but I have nothing at all against those who do buy them. Maybe they can convert me by buying one for me :twothumbs