I bit the bullet, and bought some at Lowes for $7.99.
First, I never see them around here, and second, they will last a long time since they are for my RV's grill, it's a mini (the RV), and I don't carry a chimney starter in it.
I, too, saw them in Lowes for $7 and change, but at HD for $3.29. I, too, picked up 4 boxes even though I have a performer! I used the cubes before I got the performer and still like them. Get them at HD while you can.