Actually - Yes there is a place for dogs at the home. They do not rely on electric power to be active, they cannot be hacked or "disabled" by forgetting to turn them on.  They provide early warning before a burglar or thief breaks in giving you ample time to arm yourself and repel or stop the threat.  They provide companionship and entertainment.  So, yes  I think dogs are necessary as they have been for thousands of years. 

However, people must choose the breed of dog that best match the function they want and not everyone need a serious guardian dog. some just want a lapdog or couch warmer - so choose wisely.