Is it legal to buy an ice cream cone from the store and then set up an ice cream stand and sell it for more?

First, almost everywhere it is illegal to see to the public if you do NOT pay for a business license from city hall.

Secondly, depending on where you live, when selling food you have to pass the Board of Health requirements for safe handling.

Thirdly, why would I pay MORE for ice cream from you, when I could get the same ice cream for less AT the store?

cone could be melt you know?

Q - Is it legal to buy an ice cream cone from the store and then set up an ice cream stand and sell it for more?

A - YES

For one cone??, it would melt too quickly!

It is, IF you are like 12 

I'm sure there is a word for exactly what you are thinking of, but in a wider view-

That's a thing. For example, Château al la Fred only makes 200 cases of Chardonnay every year. They only import to the USA 6 cases. 3 major importers only get 2 each. So one dude buys up the 2 cases from the wholesalers and sells them at his rare wine library at a 300% markup. That's just business. The not-so-subtelty between that and running a Mark and Donald who just buys 45 Big Mac's a day and sells them at their food truck 3 blocks away is clear. The legal permissions or violations other than the obvious are not clear, although very likely frowned upon if not outright illegal. The branding I think would be the issue. Special Sauce is a protected brand just as much as getting rich for stealing a song from your former bass player. 

i would hope not