Is Glasgow University dominated by Catholic students and Catholic values?

I'm asking this question because recently the son of a Catholic friend of mine did very well in his exams and was offered unconditional places at Glasgow and St. Andrews Universities to do the same courses. The lad chose Glasgow on the pretext that it would cost too much too keep him in lodgings at St. Andrews. Yet, given that St. Andrews is a more prestigious university than Glasgow I am wondering if there was perhaps another reason for this young man's choice.