our original "couples class" the instructor kept doing that, initially to me and for the wife the entire time. I got really pissed about it, really quick, and he figured out pretty quick that I might not know flying target shooting but I'm ok with a gun (I think it was the Sordins, and then at some point he says "you're shooting in kind of a tactical stance" :P). For the wife, it was actually really helpful in that context since it was one less thing she had to think about. At several subsequent outings I continued to load for her, but now she does it all herself.
I wonder if the Brits are doing that out of some sort of bougieness or if it's just a matter of the range folks thinking "oh christ, let's keep this inbred royal hemophiliac from shooting off their own foot and bleeding everywhere."