Recently, citizen science projects take a big part of the scientific community all around the World. Thus, non-scientists can meaningfully contribute to scientific research. Is it a good thing?
In astronomy, amateurs have been contributing to science by valuable observations for decades. Of course, the possibilities are limited. "Big science" (with very large telescopes, space flight, particle accelerators etc.) can not be realized by amateurs/citizens.
Great, the same for photographing wildlife species, people helped scientists to record the existence of some species in some unfamiliar areas. Otherwise, and in addition to what you have mentioned, citizens may have a lack of experience to give a reliable product to the scientific community.
The term Citizen Science is an arrogantly dismissive label assigned to non academics by academics. There are many non academic people doing very good science as an adjunct to their careers. The work should be treated as any other science, reviewed and utilized based on it's process and merits rather than the author's affiliation.
You are right, I know some associations doing a great work, but they can't publish and get a review. The question is : As we are academic scientists with affiliation, shall we go down to the citizens or we must bring them up to the methodological level of standardized science? Accept it or not, the majority of normal citizens can' t give a reliable scientific product as we must review and accept!
The Control should be done from scientists but in a creative atmosphere! Sometimes, we need the out of box ideas, free thinking far of regular concepts! We need the innocent questions and the view from outside the frame.