"Why the employers statistics? I can see that they are relevant to some people at some companies"
It is much more than that. Individuals can influence and promote the hardware vendors which contribute towards their operating system of choice compared to others who refuse to cooperate or actively work against it.
Customers who rely on support contracts from commercial distributions know who is likely to give them higher value by moving free software in the direction that they would like.
More importantly, given the increasingly high influence of commercial vendors in the world of free software, a better of understanding of the commercial ecosystem is critical to take advantage of our better strengths and address our weaknesses. It is statistics such as these that help us understand how Linux kernel is progressing in attracting the participation of embedded manufacturers which is an area of current interest. Overall, I and I am sure many others would as individuals find these stats important.