A lot of CrossFitters have shoulder problems. The reason for this is usually a prior imbalance (due to activities of daily life) coupled with poor form in workouts and neglect of substitutional isolated exercises.
Some may argue, that isolated training exercises aren’t “CrossFit”, but neither is Yoga. We still do it, because it helps us stay flexible for CrossFit. Isolated movements can help us train weak muscle groups, that can then contribute to the functional movement.
While an imbalance in the shoulder position won’t necessarily bother a person that doesn’t work out, it will surely show up once some load is added in form of training over a period of time.