What is the ruling on holding lectures in markets and complexes where corrupt young men and women gather?

Holding lectures in markets and commercial centers is a good thing because there are people who cannot be invited to and informed about the religion except through them. The Prophet, peace and blessings be upon him, used to walk in markets and complexes and invite people [to Islam]. Thus, the presence of corrupt individuals does not prevent da'wah (invitation to Islam) in these places; rather, it is one of the motivations for focusing on conveying the religion to them and admonishing them. The lecturer should explain the ruling on free mixing and its disadvantages, as well as the corruption that these places contain.