I understand your concern about the children of your locality and I am so proud of you that you are planning to take some action against this exploitation. Here is my advice:
Several laws in India protect children from abuse, exploitation, and neglect. Firstly, Article 21 of the Indian Constitution ensures that each and everyone should have a right to life, which subsequently encompasses the right to live with dignity. Any kind of exploitation, also in the case of children, is prohibited under this Article and you can seek legal recourse under this Article for the protection of the street children of your locality.
You can also move to the court as per Section 75 of the Juvenile Justice (Care and Protection of Children) Act, 2015 as it tends to criminalize all forms of cruelty towards a child, stating that if any person tens to abuse, assault or neglect any child then he is liable to face severe legal consequences, which will subsequently include imprisonment.
Here, in this case, the shopkeeper may face serious legal proceedings for the act he has done, you just need to file a report at the local police station or you can also move to the Child Welfare Committee of your area as it is empowered to handle such cases, involving the harassment of the children in any form.
Additionally, you can also move to the office of NCPCR (National Commission for Protection of Child Rights), stating the provisions of the Protection of Children from Sexual Offences (POCSO) Act, 2012.
I know that POCSO specifically deals with s*xual offences but this act also supports and provides protection of children from all types of abuse and protection. NCPCR will surely respond to this matter as they primarily focus on safeguarding the rights of the children and protecting them from any kind of abuse and exploitation.
As per the case of M.C. Mehta v. State of Tamil Nadu (1996), the shopkeeper will face serious legal consequences for his acts as the Supreme Court has made this a mandatory duty for the state to prevent child exploitation, and take serious actions against the cases of child abuses.
I would like to suggest you please file a case against the shopkeeper so that he will never repeat this type of act as the children of today are the future of the country.