But, it's not working !
I understand not everyone on here is a fan of remote collars. I'll also try to not take offense. But I am not simply a guy who purchased one, slapped it on my dog, and am now blasting him whenever I don't like his behavior.
I am trained to use it. I never use it when he is interacting with someone physically. It is used when he disobeys a command, and most of the time, a verbal correction is all that's needed.
Like you suggest, he gets massive amounts of treats when guests come over.
Without being critical, you might try some different things. Allow something's and disallow other's. My hand may be stronger then your trigger finger. Children are not a threat to a intelligent animal..