But the cost of obtaining the info is already incurred, for paper or ebook, correct? The method of obtaining and gathering the data is a set cost and can not be avoided. Once the data is gathered, then the method of production of the data (video, ebook, paper) is the point where it diversifies and the cost increase based off the method of presentation of the gathered data.

My collection is primarily dealing with Illegal Casino strictly from Texas (Chips, Dice, Slots, Ashtrays, etc.) and plaques in general. Most of my collection has been purged of things not dealing with these areas but I would be still interested in getting ebook versions of the publications I deal with. I would have a paper version for the bookshelf and a ebook version for the iPad. Therefore, my reference library would have both copies even though those areas outside my personal collection preferences.