I am not an advocate of a 22 for selt defense if you can use anything else bigger.
With that said I do carry my LCR-22, 617 S&W, and 4" MK III some of the time, as does my brother. Not everyone who conceal carrys does so worrying about being jumped by thugs. I shoot my concealed carry handguns several times each year while carrying. I shoot Copperheads, CottonMouths and Rattle Snake If I get the chance to. Then we have a deer or whatever seriously injured my vehicles that need finished off. An Armodillo now and again, etc. I find lots of things to shoot at over the course of a year in my rural area. Not to mention plinking opertunities.
I live in a low threat area, and I still carry daily.
I shoot in Defensive Pistol and 2 gun matches. We have a Rimfire Division in Defensive Handgun, and the 22 is a legal BUG round also. In BUG I normally shoot both my 442 and LCR-22. I shoot my MK III and 617 in Rimfire Division some also.
In 2 Gun I shoot my MK III and a Tactical Solutions AR15-22 Upper. We have lots of rimfire entries just due to ammunition expense. Normally everyone makes multiple runs on the course. We charge $10 for the first entry, and $5 for all additional entries. Almost everyone makes atleast 3 runs.
As range staff I get to do my fair share of target pasting. We double tap all targets in the match. The rimfire shooters will have lots of double tap rounds that a single target paster will cover both bullet holes. Not common at all with centerfire.
A 22 can get the job done with multiple hits.
For a survival gun, you can afford to have enough 22 rimfire on hand to feel well armed. Most of us will never stock pile enough centerfire for any serious long term use. Just a matter of $$$. I just picked up another 550 pak of Federal last night at Wal-Mart. I was not low on shells, I just picked up another box, they store well in a Fat 50 ammo can.
The 22 is not a bad choice to carry in a low threat area, where varmints are the main targets of your rounds.
Better close and head to the Gun Show.