My child often goes to school without breakfast whoever mentioned that one.
Not because he has a Mother who is feckless and can't be arsed or always running late. But because sometimes the stress of actually leaving the house consumes him he can't eat or perhaps because it is the wrong sort of day for eating breakfast or because it takes so long to put clothes off and on because they are touching too much. (see above we are awaiting ASD diagnosis)
But yes 9 times out of ten he has no breakfast, the smallest packed lunch (but healthy) he can get away with until he can get home and eat in comfort. He doesn't get social eating sees not one ounce of enjoyment in it, it is stressful for him, food is just a pain to him and mostly he doesn't like it. So no way would it improve his daily learning, though I appreciate for many it will, that I can understand. But removing his choice so that "everyone" feels better al eating the same together, instantly stops him from feeling better, so someone is still suffering. I imagine this will be very similar for many ASD kids. (not just them but using it as an example)