Wedding photography has a very well established business plan where the base fee covers the basic costs of the photographer, and the prints supply the profit. You are not paying twice for the same thing - the real cost has simply been split up in a way which is convenient to both the photographer and the customer. As it is not exactly an uncompetitive industry, and you don't see many wedding photogs turning up in Porsches, i'd say the pricing and model were pretty fair.
The reasons for the model relate to the photographer having control over his/her reputation, not to screwing the customer - when photos were still taken on film, the quality of the final print had as much to do with the printing process as the actual taking of the picture. Retaining control over that was important to the reputation of the photographer - if he actually handed you a stack of negatives and let you have them printed by any old mail order company, the lousy final prints would impact his reputation. You *could* argue it is an outdated model now, with the rise of electronic media, but most couples still want prints, and the same problem actually still remains - giving out jpg's and letting people print at home or from a cheap online outlet is going to result in exactly the same quality/reputation problem as in the film days.
The industry is adapting to modern times though, so you will now find some wedding photogs will include a DVD of low resolution images for you to put on the web (and many will host a web presence for you as part of the package). But any you find who are willing to give you full size images and reproduction rights for anything less than a big pile of money are probably not the quality of photographer you want covering your wedding anyway.