Can it be said that in so Christian churches idols are worshipped?

It depends upon what is meant by idols. In any case pure worshippers of idols in any religion are rare indeed. When the early Christian missionaries found various cultures using images as symbols of certain concepts they wrongly assumed that it was the idols themselves which were being worshipped, rather than the concept they symbolized. They never bothered to look beyond what they saw. Similarly the images and statues displayed in certain Christian churches and before which people kneel in worship, symbolize a greater concept than mere idolatry.