Putting cash money or any other prizes inside food packages or any other goods
The principal ruling is that it is not permissible to
put cash money or any other prizes inside food packages or any other goods, because this involves cheating people and attracting large numbers of clients and swerving people from buying other products which do not contain such prizes. Buying milk packages containing various amounts of money with the main aim of getting that money is not legally permissible. Rather, it is a form of gambling which Allah prohibits because it involves fraudulence, uncertainty, and Riba (usury/interest), as the client hopes to restore some of what had been paid or even more than it. This is Riba in which it is prohibited to deal, (Part No. 11; Page No. 179) because ignorance of equality (between articles of the same type) is like knowledge of inequality (between articles of the same type) and both are prohibited. So, it is not permissible for you to take the money you found inside the milk packages. You should better return it to the suppliers of this milk if it is easy for you to do so; otherwise, you could get rid of it through giving it in charity to the poor and the needy.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.