Guns can do better, yes, but better for both sides, which is the problem. And if they are the ones who stay when knowing you are home, arent they the ones also more likely to have guns as well? And if they are bringing guns into a home invasion/robbery, that means they will probably not flinch at using them. So you having access to guns means that they also have acces to guns, and you get a escalating situation, whereas a lack of guns means you and them have to get close to fight, giving both parties a more cautious outlook on interactions, as you/they won't do something stupid/reckless on the assumption you/they can fire first and avoid injury.
Zakharra wrote: Guns can do that better and most burglars will leave if they know there is someone in the house with a gun. A certain subset will not leave, but they aren't the majority and for the most part arms (most people think of guns, but arms is -any- weapon) are something people can use to defend their homes. If someone invades my family's home to steal from it, if I can, I will use what weapons I have to dissuade that person(s) from doing what they are. Probably by shooting them if I can or sticking them a few times with a sword or two and making them wait until the police can show up. Either way I would do my best to make sure they regret setting foot in our house.
As it is though, most burglars will try to strike when no one is home specifically because they don't want a confrontation.