My son sent me a link to a Facebook page concerning peanut butter. Apparently some peanut butters are now being sold with xylitol used as a sweetener which is toxic to dogs. Since peanut butter is mega calories I cannot imagine why anyone would opt to use a sweetener
I use peanut butter to block the end of the Kong, I believe there is a list somewhere of the brands containing xylitol but I always check the ingredients when I buy it. But you're right why it needs any additional sweetener I can't imagine.