I think your neighbors are totally out of line to let their dogs run free. However, I can't blame someone for avoiding talking to you and not apologizing to you after your husband's reaction was to threaten shooting--not something more normal like reporting them but, shooting them.
I know you came back later and said you would not really shoot the dogs, but how are the neighbors to know this? I find it very odd that you are willing to threaten to shoot and kill the dogs, but not willing to report the illegal behaviour and let the authorities deal with it.
Reading on, it seems once you did report that the neighbor was a complete jerk. That'S too bad, living near such people is always trying. It just seems like your husband was also quick to be aggressive and unneighborly as well---both sides making the situation worse than it has to be.