I'm sorry, but I just don't understand how it is hard to use...sure, tables might be a little difficult, and having images how you want them too, but for simple editing it really isn't, especially with the edit bar.
[shrug]
It isn't hard for me either. And do you REALLY use the edit bar? I'm guessing you don't - as most contributors don't.
But how many non-techie wiki users do you have to support? I directly support, oh... about 300+ contributors spread over about 100 wikis. I've given several presentations on wikis and several hands-on instruction sessions on editing. I've written custom articles on how to get started with wikitext editing and given direct email support.
At a minimum, 50% of those contributors are still handicapped by wikitext, and another chunk of people simply don't contribute at all due to wikitext.
- MHart