Did permit actually neccessary to open a food/drink stall in America? I'm not 'Murican so i'm ignorance about the subject.
Technically. Would depend on the specific county, but I believe you technically need a license in most parts of the country (Disclaimer: IANAL). The authorities don't (historically) usually bother enforcing the requirements though, especially for lemonade stands ran by little kids, but recently (like in the past decade) there were some noticeable spats with kids getting fines or warnings, like some cases in New York, California, Iowa, and I think Georgia.
Oh and a tyke got fined across the pond too in Dear Old Blighty.
It's probably the same in most countries as well; you need some sort of permit to sell food and drinks, for health and safety (and revenue) reasons. It's just that the authorities aren't that particular on enforcing in against small stalls, especially when they are ran by kids, but as times get on and society gets more 'advanced', they'll start getting more and more punctilious about enforcing regulations.
(Because if someone falls sick, there's greater demand for accountability [Someone falls sick from improperly-prepared food/drinks? Better sue the kids' family and the local council then!], and treating sick people becomes more expensive. And to be fair, usually the process of getting a license is expedited for small, temporary stalls [in places where they do bother enforcing it for such stalls].)
Did permit actually neccessary to open a food/drink stall in America? I'm not 'Murican so i'm ignorance about the subject.
Generally yes, plus add in a few regulations about food safety depending on your state. Like I know if you work with food in anyway in my state of California you must take a course and get what is called a food handlers card.
It is generally up to local governments whether or not they enforce the need for permits on kids and the like, but as the years go on it seems to be getting more common.
Also depends on "Where" you plan on opening your stall. A kid opening a stall in the suberban neighborhood? Most police would just think that's cute. But on a busy street intersection in the middle of the bussiness district? Hells ya you better get a permit.
Also some regulation may be needed in case children are being exploited by their family to sell the family's produce. Not so much in developed countries, but somewhat of a danger in a few cases in some desperate underdeveloped places.
If China's present smogs can be matched by Britain and America in more pollution-friendly times, we also worked children to death under early capitalism, so it's not just the Third World. And even today China has child labour in factories.
I may not look like it but I do have confidence that my lemonade will sell, admiral.