Don't Tell the Bride - am I just not "getting" it

[Saltire]

Surely if the couples on it have been together and are actually engaged thenm they will have talked at some point about what they'd like their wedding day to be brides especially - I'd like purple bridesmaids dresses,I'd like to get married in a big mansion etc

I think the producers ensure that some "bad decisions" are made for viewers pleasure other than that I'm sure it's truelly authentic and not at all manufactured