I'm not a fan of free feeding (or, leaving it out for the dog to eat whenever) for a number of reasons. My dogs, and those I foster, eat what I put in front of them, or go without until the next meal. Of course, I keep a close eye on them, but, it's never been a problem except when there was a medical issue. Dogs pick up on our emotions more than one might believe. Food is a biggie, and I'm amazed by the problems that people encounter with feeding. Unless there's an underlying issue - like a bad tooth, or disease - a dog will accept and eat what s/he is given.