When you live with a pet, who eats what food is a bit of a democratic affair, not an autocracy.
Do you want to get up from the middle of a movie to go to the bathroom and come back and find that you're not going to find out who killed the leading lady tonight because you're going to spend all night in an animal emergency room getting your dog or cat's stomach pumped?
Anything on a table or in your purse or your jacket pocket is fair game.
Monkfruit doesn't come in a nice, familiar crystal form, and monkfruit extract is much sweeter per gram than sugar. For this reason, manufacturers bulk it up with some kind of sugar alcohol to make it easier to use. GP is saying they use erythritol for this purpose because the other options (e.g. xylitol) are toxic to pets.
I love fishermans friend, but I think the sorbitol is guaranteed excessive flatulence.