My significant other is absolutely right about almost everything.

Not this time. You win, but correct her with great humility!

Anyway... do any of you see any harm from leaving crumbs of wood... or
even a log of wood outside my back door?

I leave a day's worth of logs on the redwood deck against my house all the
time, and the deck structure and siding are both wood. No, termites don't
get "attracted" by a few crumbs. It is however a good idea to keep
sufficient space between the woodpile and any structure it sits next to. My
main woodpile is under 3-foot eaves, sitting on brick path, and held off the
ground by cross- pieces, with a 6" air gap between the wall next to it.
Also, keep wood on a dry, well-drained spot. I also criss-cross the wood to
hasten seasoning and keep it dry and well drained. Continuously wet wood
will eventually begin to rot, and in that state it becomes very attractive
to termites.