Only reason for me that I brought up the table scrap issue is two fold for me......my previous Lab and his brother both developed diabetes after about 4 years. My sister/brother in law had young kids and Mom would watch them alot. Mom also watched both dogs alot. As it played out, the dogs were getting alot of human food, whether it be from the kids messy-ness and clean up by the dogs, or the kids giving them food, or Mom giving then what may be left.
The dogs came from quality bloodlines on both sides with no history of diabetes. None of the other 4 dogs in that litter developed diabetes. Long story short, the only conclusion or explanation was that it was related to the excess human food they were "getting" and the "sugars" in that food. Both dogs were blind by 6 or 7 from the diabetes, which lead to other health issues. Was crazy and tough.
The other reason, is simply I don't want my dog to even consider getting a morsel as an option to start any bad habits.
I have given him fresh garden vegetables such as green beans and such, outside of the house. Mine loves fresh green beans and can be used as a training reward or treat too.