Call me crazy, but I'm planning to use them when I bottle a batch of wine in 22oz bottles.
I have a lot of empties, and a capper, but no wine bottles, corks, or corker.
I will also use them when I bottle the 9-9-9 and remnants of my Christmas beer using a BMBF since those will be pre-carbonated in the keg.
For normal bottle conditioned beer they don't seem necessary, the yeast will consume the O2 in the neck.