Is archaeology important or is it just a middle class interest?

Yes if it gives us an understanding of the past but if in the end it destroys in pursuit of knowledge - no. Something I read on by the chief archaeologist hosting the irish motorway, to vaguely quote cos I can't find it

"We do not use the term destructive archaelogy anymore but "deconstruction", so presumably if people want the stones at Avebury re-erected it becomes constructive archaeology...