I have a Saint (St. Bernard). I don't know who posted it, but whoever posted that about the bigger the dog, the more liable the owner is and the greater need for responsibility is dead on. A Saint isn't a chihuahua, even if it is far more friendly. I'm 5'7 and 200 lbs, and when Cassius jumps on me he'll knock me down. Imagine what that would do to a 5 year old or 70 year old. So I'm very careful about socializing him and always have him leashed in public, not because he's mean, but because his friendliness paradoxically is dangerous. I think that people whose dogs bite someone else should be prosecuted fully, there is no reason for this, and the "accidents happen" thing is too little, too late. While an attack from my dog may prove fatal, I have been bitten far more by small, yappy furballs than by any larger dog. Most attacks probably come from smaller dogs, most fatalities probably by larger ones.
As to people taking their dogs with them, I'll take Cassius to PetSmart or PetCo and let him go inside. Often I'll take him in the pickup when I'm just going to the store or a short trip. Taking him to a restaurant or voting might have logistical problems. Most of the people I see taking their dogs into grocery stores, restaurants etc., are either very young women or very old women. I've never asked their political persuasion. I don't like a dog hanging over the meat counter, it just seems wrong to me.
