I am a size 3X/4X depending on the style, and most patterns, free or not, are not written for me or others like me. I am a member of the Plus-Sized Crochet group in Yahoo. We are 674 members strong at this time and membership is increasing everyday. The lack of plus-sized patterns is the primary focus of this group and of other similar groups that I belong to on the web. Also, we teach each other how to enlarge the patterns, if possible.
I can only imagine how many like minded and plus-sized persons there are who do not have access to such forums. Just the fact that whatever we make for ourselves will require more yarn than is needed to make smaller sizes should inspire you to address this issue for the benefit of your own bottom line.
With the constant barage of surveys showing that the public is not a size small or medium, like so many models are, it is surprising to me that so many companies ignore our buying power. Help address this issue by requesting that designers think about us when they create patterns.
Links:
[1] http://crochetme.com/forum/how-do-you-hold-your-crochet-hook
[2] http://crochetme.com/forum/confused-about-copyright