Reading the article, I think some of it is more of a "why?" than a "why not?", since the articles are factually correct but are mostly just lists of facts and not really something you couldn't find in any number of other resources.

For people who do serious article writing, I imagine this might be considered as a "cheapening" their work. For instance, I imagine some editors also resent the notion that encyclopedia editing is somehow reducible to plugging facts into the right templates. Of course the bot's authors don't really believe they are creating articles as high-quality as good human-edited entries, but the emotional reaction on the part of other editors is at least something I can comprehend.

I'm not really in tune with Wikipedia, so this is mostly conjecture.

edit: reverted edit, added first sentence of 2nd paragraph.