I think the hogging at the top of the mane is to do with breed turnout, as No_Angel says, it's really common with Arabs even in the high level showing in the UK. The clip is possibly to do with it being a youngster as well, in the UK I think (don't quote me on this) you can undertake limited clipping on the finer youngsters i.e. bib type clips for winter showing....you don't tend to see it done quite like that over here so could be the US version/how that breed are clipped?