I'm not a fan of pumping babies full of all kinds of things. I like to keep it simple. I've seen the aftermath of a baby that grew too fast and ended up with lameness issues.
I think that you have a point there. Horses have evolved over tens of thousands (millions if you include proto-horses) without the need for supplements. These kinds of things are there to create a market, regardless of their claims, they are not there for the health of horses, they are there to make money. If the people selling them can create the appearance of a need for them they make money.
Yes, but horses evolved as free ranging animals that traveled miles and miles AND MILES to find food, water, and necessary and naturally occurring vitamins and minerals in the form of vegetation naturally fortified with what they needed, and includes eating or licking soil, clay, and rocks for certain minerals they were deficient in. As humans domesticated and fenced horses in comparatively tiny areas, we took away their ability to self supplement. Doesn't mean they weren't getting supplemented throughout their evolution, it just means humans didn't do their supplementing in the form of a horsey multivitamin, or ration balancer, like we do today, they had to search their environment for individual sources by way of their instincts. I feel it is my responsibility to provide vitamins, minerals, and adequate forage because I am unable to offer a completely natural environment for my horses where they can travel and forage for themselves, the one they evolved to live in.
After starting this my gelding in particular has improved tremendously in foot and body condition. But he does not get a fortified feed as I feel the filly needs, he gets his joint supplement, Dynamite (vit/min sup), 1/2c flax, excel (digestive catalyst) and dyna-pro (liquid pre/pro-biotic) once a day in addition to the free choice minerals and salt, and of course free choice grass hay in a CC net.