Eleusis - I would be concerned, perhaps, if the CoE wanted to build "a whopping great Anglican catherdral three times the size of St Pauls" in Stratford, East London. In the case of football grounds, I wouldn't want one built in my close neighbourhood, either. I don't se this as some sort of international tit-for-tat as you do. Either a whopping great building attracting huge numbers of like minded people to an area is a good thing, or it isn't. And in this very case it seems to be established small local mosque communities that are protesting.
Planning law will look at the design of the building (hideous, from the scanty computer graphic shown) and it's impact on the area in terms of user numbers and noise etc.