Few songs sell well at retail without it.
None sell millions without it. The two types of stations are treated very differently as far as airplay is concerned. There are approximately 10,000 commercial stations, and 2,500 non-commerical stations, in the United States. The first chart is an average of many stations, while the second chart is from just one station. If you are hiring an airplay promoter, then you do not need to subscribe to CMJ or other charts, but you do need to know how the charts work.