I have yet to read where a civilian CCW'er has needed more than 5 shots, and indeed, the vast majority of self defense shootings involve about 3 seconds with 3 shots fired.
If I need a reload, and have time to reload, I'll be getting the hell out of there.
The reason for a reload is for multiple attackers or because of a malfunction.
Say you are facing three attackers with only a 5 shot snubby. If you fire one shot at each of them that only leaves you with two rounds in case of a failure to stop. What do you do if you miss one or more of them with those first three shots, they continue their attack, and you have no way to escape? It may be unlikely to happen, but it could happen. If you are unlucky enough to get in a situation like that, there will be no such thing as too much ammo!!
In the case of auto-pistols, most malfunctions are due to a faulty magazine. So the easiest, most efficient, and quickest fix is to drop the offending mag and insert a new one, and I have heard about this happening. I've also had it happen while shooting on the range, so I switched mags and that fixed the problem. If you only have the one mag that is malfunctioning, well all I can say is, I sure hope you practiced your malfunction drills a lot.
You may not have heard or read about anyone needing their reload, but that doesn't mean it doesn't happen.
I just don't understand what the big deal is to slip an extra reload into your pocket. I ALWAYS have at least one reload, and it has never bothered me in the least to carry it. To each their own I guess, it's your life, and odds are you will never even need the rounds in your gun to begin with, much less a reload. However, I for one do not want to find out the hard way if I'll ever need a reload or not, so I prefer to always have one. It's the same as carrying a gun in the first place, I'd rather have it and not need it, than need it and not have it.
IMO, if you are not going to give yourself every possible advantage you can, which includes carrying a reload, you probably shouldn't even bother carrying a gun in the first place.