Hmm, I'll have to check that out. Check out my media price thread in Memory and Storage.
I picked up some Ritek 4X BD-R white printable 50-pack spindles for $16.99 at Newegg recently.
But I guess if you only need a few or something...
Edit: Is the name of the store literally "The 99cent store"? My local Dollar Tree didn't have any BD-Rs, but they had plastic-wrapped packets of three CD-Rs for $1. $0.33 for a CD-R, not quite worth it, unless you only need a few.
Thanks for posting this though, I'll keep my eyes open for them.