Just to clarify, no-one is saying that they can't eat it or won't, the link provided explains the following:-
Remember: a rabbit is a lagomorph, not a rodent or a primate. The rabbit digestive tract is physiologically more similar to that of a horse than to that of a rodent or primate, and the intestine and related organs can suffer from an overindulgence in starchy, fatty foods.
NEVER feed your rabbit commercial "gourmet" or "treat" mixes filled with dried fruit, nuts and seeds. These may be safe for a bird or hamster--BUT THEY ARE NOT PROPER FOOD FOR A RABBIT. The sole function of "rabbit gourmet treats" is to lighten your wallet. If the manufacturers of "gourmet rabbit treats" truly cared about your rabbit's health and longevity, they would not market such products.
Don't feed your rabbit cookies, crackers, nuts, seeds, breakfast cereals (including oatmeal) or "high fiber" cereals. They may be high fiber for you, but not for your herbivorous rabbit, who's far better able to completely digest celluose ("dietary fiber") than you are. Fed to a rabbit, the high fat and simple carbohydrate content of "naughty foods" may contribute to
fatty liver disease, cecal dysbiosis, obesity, and otherwise cause health problems.
A SPECIAL NOTE ABOUT CORN AND OTHER SEEDS
Some types of seeds (especially things like "Canadian peas" and corn kernels) have hulls that are indigestible to a rabbit, and can cause life-threatening intestinal impactions/blockages.
Corn, fresh or dried, is NOT safe for rabbits. The hull of corn kernels is composed of a complex polysaccharide (not cellulose and pectin, of which plant cell walls are more commonly composed, and which a rabbit can digest) which rabbits cannot digest. We know of more than one rabbit who suffered intestinal impactions because of the indigestible corn hulls. After emergency medical treatment, when the poor rabbits finally passed the corn, their fecal pellets were nearly solid corn hulls! Those rabbits were lucky.
Individual choice what you feed your rabbits and if anyone would like to challenge the findings of this report go ahead.