I don't see what domestic violence has to do with round count. What does have to do with it is the fact that regardless of the encounter, today more than ever we are probably going to be facing a threat that is on some type of drug. Heroin, pills, meth and all sorts of synthetic drugs are abundant in almost every city, so the likelihood of the person attacking you being artificially stimulated is highly likely and history has shown us that many times these drugged individuals are bullet sponges. I've literally read numerous OIS Duty reports where suspects were still attacking officers and resisting arrest after having basically their guts blown out. I don't mean to get graphic but Chunks of tissue hitting the ground, blood pooling so thick you could smell it, entrails hanging out in plain view but still fighting. This type of individual is not limited to encounters with just police, and they may just pop up at your car window one day while you're at the ATM or as you are loading up some groceries. In the event you should encounter someone like this, do you really want to rely on 5 rounds to do the job? Do you really want to rely on a little .22 or something to do the job either, when majority of the time even large calibers dont do the trick? I certainly do NOT, so I carry a caliber I am comfortable with and a platform that has decent capacity and the ability to reload quickly should the need arise.
If all you can comfortably carry is a little mouse gun or 5 shot .38, its better than nothing for sure, however if the only reason you are not carrying more rounds is because you think it's totally unnecessary then you are just fooling yourself. There will be plenty of opportunities in life to deal with unexpected things when you aren't prepared so in my opinion there is no reason to temp fate and throw more caution to the wind when it is so easy to just be a little prepared.