Good writing - how much does it matter?

Obviously, to many people, not much. To them perhaps the story is all (or nearly all), and that's what matters. And that's fair enough. After all, writers are trying to give readers what they want, not competing in a competition for the best syntax or grammar. But...

I mind desperately. For me, the writing must never get in the way of the the story. It must flow smoothly, almost unobtrusively, so that events and images are built up seamlessly in the reader's imagination, with no unnecessary intereference.

If I come across bad, or obtrusive writing, it's as though the fabric of the narrative has been snagged on an obstacle; my involvement in the story is held up, while I wonder why the author used that odd phrase, or that strange piece of description.

Some examples from a novel I've just read:

A frown invaded his features. Why not simply, "he frowned"?
He heard the breath of her grin leave her mouth (????)
The girl...leered at him, her head doddering on its axis like a nodding dog (WHAT?)
Someone turning off a computer message silenced it with an emphatic digit (turned it off?)

In the same novel, characters don't just "say" things; they snarl, spit, growl, sneer and scowl their words. Why? Shouldn't what they say speak - literally - for itself?

Maeve Binchy, who sadly died this week, and who told wonderful stories in simple prose, believed this kind of thing was quite unncessary. So do I.

What do you think?