If you don't sell your goods or services at a loss, then you're "greedy". It might be helpful if every child is encouraged to have a lemonade stand where they themselves have to pay for all the ingredients, cups, ice trays, pitchers, cardboard, magic marker... maybe then folks would have an appreciation of basic economics.
Nonsense. Nobody begrudges someone making a profit.
But blatant greed is well known to happen and while it may be legal, it isn't right.