Ha! I stand corrected.
(It'd be nice if publishers would use that language, too. "Due to current economic conditions since forever and the industry-wide decline in overall book sales since Gutenberg, we will no longer keep the policy we have followed since Day One and not accept unsolicited non-agented queries and submissions of any kind from previously unpublished authors.")
Well, erm, no, that's not what Stacia meant. She was talking about it being 'since forever' that celebrities get big advances. That's what's not a 'current economic conditions' issue.
As others have said, the title of this thread has absolutely nothing whatsoever to do with the original post's actual content.
The reason that so many publishers have stopped accepting unagented submissions is because, due to the ease with which manuscripts can be put together on computers (vs typewriters, which was one hell of a lot more work), they started drowning in unpublishable crap.
It has nothing whatsoever to do with allocating more money to celebrity books than they did previously.