Hi all.
I work for a publishers and I deal a lot with usage rights and copyright licencing.
It virtually unheard of for a photographer to surrender the copyright without invoicing a LOT higher rate. Usually 3 or 4 times as much, 10 times the rate is not unheard of.
With the exception of a few rare specialist circumstances there is no reason to obtain copyright. As standard all you need is a 'usage rights agreement' and as long as the usage rights agreement covers your required usage, such as printing or putting them on your website, or whatever else you require then all is fine and you don't need the copyright.
We'll often licence images on an 'exclusive' basis, but again this is not copyright.
(its very unlikely you'll need to worry about this for wedding photos)
Transferring of copyright is so rare, without a huge payment, that if a photographer offers it to us, we often assume that they do not know what they are doing, are a complete amateur and simply refuse to deal with them. Same as we won't deal with amateurs who offer un-colour calibrated images or un post processed photos.
If you actually ask most amateurs about image rights / licencing / post processing and colour calibration most have no idea what you are talking about or try to bluff their way through telling you that don't need them.