To my mind it is strange, but there are some people who have some sort of weird obsession with the aspect ratio that the camera they are using produces. They think there are certain "rules" that everyone must follow. One of them is you should never crop. Bizarre, right?
Is the 35mm (3:2) aspect ratio a crop of the 6x6 frame? Or, is the 6x6 a crop of the 35mm frame? Or, are they both crops of the 8x10 and 4x5 frames? How about 6x7? Which one is it a crop of or are the others crops of the 6x7? It is all so confusing!!! How about 4/3? Oh, it is such a can of worms worrying about photography "rules"! Makes my head hurt. Which one of these is the "true" aspect ratio that all photos should conform to???? For those inclined, maybe Jesus, Buddha, Allah, et al will enlighten us. For others, maybe astrophysics will someday provide the cosmic answer.
Until the "truth" is revealed I am not going to worry about it. There is nothing sacred about the particular aspect ratio that the hardware imposes. If you want a square image but your camera doesn't produce it then crop. Vice versa. Let your imagination be your guide as to how, when, or if to crop. That is my opinion.