The UK has strict rules on where you can have your ceremony, regardless if you are hetero or gay, and every place that is allowed needs a very expensive license to have it on the premises. This means you can' really go too crazy on where you have it.
Not all churches are homophobic, as the article show. More than a dozen church organizations support gays and gay marriage, but are banned by law from doing them under the guise of religious freedom.
The other aspect is, gays are banned from marriage FULL STOP, not just religious ones. So it's not just about religion, as we're banned from secular marriage as well.