I think it was more that King sold them on the idea the wedding was going to happen, and then DC promoted the hell out of it (with a gazillion variant covers that could be ordered specifically for individual stores, etc.), only to yank the table cloth off A FEW DAYS BEFORE THE ISSUE WOULD BE ON SALE IN STORES!
It just seemed like a totally crass move the way DC went out of its way to promote this when they knew damn well what was going to ACTUALLY happen in that over-blown issue. All they wanted was the $$$'s and publicity. Screw the fans / readers / retailers who had been supporting this.