"We need gravel -but from Thornborough?"
No we don't. We would LIKE gravel. We would like gravel to build homes, roads and other such things. There are alternatives that would improve our lifestyles enormously, but they wouldn't make anybody much profit.
"And we need wind power - but from Callanish?"
The people of Lewis and northern Scotland need electricity, yes. They don't all still use candles up there you know :-) Many do rely on generators though. Locally produced power would be a great thing for them. It's the way the future will have to be anyway, so we might as well start getting used to it.
The fact is that to sustain our lifestyles (not necessarily a good plan) we NEED electricity and the west coast of Ireland and Scotland could provide around 25% of Europe's needs or some such equally ridiculous figure.
The comparison between Thornborough gravel and Lewis wind power doesn't stand up. They're nothing like each other.