Avik,
If you would have followed even your part of the conversation, you would have seen that it was referring to how soaps, including laundry detergents used to be made. And there was no real difference in the soaps then, they were used as both laundry and other detergents.
And I am pretty sure the olden day soaps were items that dogs could and would eat, self respecting or not.
Akuperma was saying that people may want a hashgocha because of what traditionally soaps were made of.