In a week or so I will be writing a blog about non-humans and morals. The Peter Singer issue. Right now I'm in Iowa and am learning as much about this region as fast as I can.

The issue of bringing dogs to dinner is slightly different from bringing dogs into grocery stores, which I have blogged about
before. The grocery store and other public spaces must make their own rules and these rules have to do with public behavior in a public space. That is different from my subject herein.
Should you bring a dog where you are going? If the place you are going is someone else's personal responsibility, the answer is that you must get permission.
We often forget that dogs and other pets are in the domain of manners (not morals). A dog is theoretically under the control of its owner, just as a child is theoretically under the control of a parent or guardian. (The obvious distinction here is with cats and nearly all other household pets and human infants).
Therefore if you would always ask whether a child is invited to a dinner, a meal, a party, a bar-b-cue, to a stay over, a short trip together or anything similar, then the same applies to a dog. The host needs to know the degree of control you have... generally measured by the age of the child or in the case of a dog, the size of the pet and your judgment.
Dogs are in the domain of manners close to the category of children.