in Mexico, and perhaps repeated elsewhere in the world, the dominance of Coca-cola can be traced directly to their policy of providing a free, serviced, high quality refrigerated unit to tens of thousands of tiny mom-n-pop storefronts on the condition that they are kept stocked and in a prominent position in the shop. In many of these shops today, and in all of them back in the 70's and 80's, it is/was the only refrigerated storage in the shop, and sometimes (rarely nowadays) the only source of chilled anything in an entire village.

> maybe 10-20% of shelves of any grocery store?

Maybe not. Not at any grocery store I go to, anyway. I might give you 5%.

They have a full isle of sugared breakfast cereal though.

I have no judgement about people eating junk (in reasonable amounts). I eat it too from time to time.

But a full isle of junk for the "most important meal of the day"?

I wonder how much sugar in everything by weight is actually sitting on the average grocery store's shelves and what percentage by weight that is to everything else, not counting packaging.