I’ve heard that, as well, that in Belgium, if a vendor only sells frites, than a Jew could eat there. In India, the Hindus are strict vegetarians. I was referring to factory production, but otoh, I did recently see an article which said that certain additives and chemicals used in our processed foods are not permitted for use in countries like the UK, where the idea of foods without a hechsher but with rabbinical endorsement is prevalent.
There are certain vegan food items that are produced in America without a hechsher that I’d like some kashrut rabbis to look into. There are artisanal vegan cheeses, vegan Field Roast, May Wah meat substitutes, and other items that would be very convenient if available kosher. Likewise, items like almond flour, coconut flour, tapioca-based GF baking mixes, etc. should be investigated, as having these kitniyot-free items available for Passover would make life far easier (imagine having a decent loaf of Gluten Free bread as an option on Pesah, instead of matzah at every meal).