I was thinking the same thing before I went on my tour.. Why such a huge handlebar bag?? I saw no need and thought it looked weird, so I got a small tubular one (Jandd, made for kids I guess) and it was perfect to hold the three essential things (for me).
Tape recorder,
digi camera,
wallet.
It had enough space to hold a power bar (never did) or a piece of candy or two. (dump a pack of starburst in there for small treats along the way)
my 2 cents, everyone lives differently. .
~Steve
eventually I moved the bar padding to the drops, where it was very comfortable. . .