Don't you "hate it" when people use "quotation marks" just for "emphasis?"

These bloggers certainly do.

Hee hee.
I guess this trend has bugged me so much that I've refused to analyze what motivates well-meaning souls to do this. Now, thinking about it, I guess it's the idea of appealing to a higher authority, e.g. very important people want you to know that these items are "on sale," see? It's not just me, the poor schmuck writing this crappy sign by hand who says they're on sale, but very important people. That is my best guess.

Thanks to Mr. X for the link.

And in a similar vein:
Apostrophe abuse