I adapted the following piece from a paragraph in Ibn al-Uthaimeen's explanation of Kitab at-Tawheed. Its quite obvious and sr. jannah has been saying it for a long time...
An important quality of the one who calls to Islam is not to go around solely labelling everything as haram or bid’ah, because this is not a teaching method that the shari’ah came with. If the caller to Allah finds people engaging in something wrong, not only should he tell them to refrain from doing so, but he should provide them with an alternative to their previous practice.
There are examples of this found in the Qur’an and the Sunnah. In the pre-Islamic days for example, one of the customs of the people was to seek protection from harm with the Jinn. When Islam came it forbade seeking protection with the Jinn and gave the people a better alternative, and that was to recite the du’a “I seek protection in Allah’s perfect Words from the evil which He created.”
Similarly, the Prophet found people engaging in types of business transactions which possessed an element of interest (riba) in them. So he forbade them from doing such and then explained other types of transactions which were halal until the people were satisfied.
To use a modern-day example, we often find that people practice lots of bid’ahs following the death of a Muslim hoping that the deceased will benefit from them. Instead of only advising such people to abandon these practices, the caller to Allah should also explain what really can benefit the dead according to the true traditions of the Prophet Muhammad sallallahu alaihi wa sallam.