Mine tried that crybaby BS a few times and got absolutely nothing while we were shopping. After they were told to mind their manners in the store and did so, they could pick something at the cashout stand. Getting something for nothing was never a question, they just got less the next time and learned early.
Also, they learned if their answer was no to a simple and useful question, clean your room, do the homework....
then they would also get a NO from us when asking to go out, get something and they learned we could say no also to their simple questions. Give and take was used. I am very proud of them both and they are trying hard to do the same with our grandkids...but times are hard when even in kindergarden the little azzholes are aggressive, abusive and negligent with the other children---taught well from millenials as parents.