Ribbons wrote:
its a fact that there are lots of of ppl for example in the public eye then, who get married at church but you never see them attend it every sunday
Part of it is probably for the benefit of family members who may think it important, even if the bride and groom don't (or bride + bride or groom + groom if you live in Canada).
But part of it is also probably that you live in the UK. Back in the 1753 they passed a law there (Lord Hardwicke's Marriage Act) which forbade secret weddings, did away with Common Law marriages, and so on; it basically put control of marriage into the hands of the government, where it had never been before. As part of this process, the government said where and how it was (and was not) OK to get married. Churches are an allowed option, many other places aren't.
In the US, for example, it's different. My first marriage was conducted by a neighbour, in that neighbour's apartment, and the only witnesses to it were her kids. I am almost certain that such a wedding would be considered invalid in the UK.