It's not so much that they don't want students who have studied that before, and more that generally, you don't need to have studied those subjects as a degree to go into that sector, and the transferable skills necessary can be gained from any degree - and some may be better developed on a more academic course. Additionally, the more "prestigious" or at least popular graduate roles will, due to competition, end up more likely to recruit from correspondingly more "prestigious" universities - and universities in general, as you go "up" with respect to league tables etc, tend to have more academic courses and fewer less academic or vocational degrees.
But it depends somewhat on where you want to go and what you want to do. Yes, if you want to get a high flying role in London when you graduate, you should realistically aim for the best university you are likely to get into - this may not then offer the course you have in mind. However if you are perfectly happy pursuing a regional role or looking more broadly at things related to your area of interest but potentially not immediately in it, then it matters a great deal less. However, it is important to bear in mind, the above is working under the assumption you would get the same classification in either degree. This is not necessarily true; if you really dislike your course and/or struggle in it (be it an academic course or otherwise) then you may find you do more poorly in exams and hence fail to get the requisite 2:1/1st required for all those city jobs. In fact if you get a 2:2 or 3rd, you may even find it harder getting into some regional roles, depending on which university you go to and what jobs you're applying to...so you should also choose based on the one realistically you're going to have enough sustained interest in to actually get a good degree result.
As something of an aside, if you're interested in the more practical elements of media production, but want to do a more "academic" degree to keep your options open, you may want to consider Anthropology. Quite a few courses have ethnographic film options or scope to pursue that even if it's not the absolute aim, which may be of interest if you want to pursue something in journalism. Additionally the cultural sensitvity engendered by that course may be less apparent in a History and/or Politics degree, at least if you don't make a specific effort yourself to pursue that line of analysis/enquiry. In terms of ethical journalism and indeed even just, accurate journalism, actually having a greater sense of non-Western social/cultural perspectives might help in that...as far as individual courses go, I'm aware UCL has film pretty well integrated into their course if you so choose, from year 1 even. I believe SOAS has options to study the critical side of that, and possibly use those methods in a dissertation as well.