Why do we strike the flint with steel, could this be an inherited thing ?
Probably more of a comfort thing, I don't particularly like striking towards my hand with a piece of "Nature's Scalpel", it's a bit like chopping towards ones own hand with a machete. What's more the flint can be a little fragile or difficult to get a really solid grip on.
The steel is normally easier to hold as well and provides a visible barrier between fingers and flint