Meanings of imagine thousands in English

I'd imagine thousands of them litter Summer.

Then imagine thousands and thousands of wives walking up and down the streets on strike, and scabs taking their places.

I do not put this forward as evidence of singular perception on my part, for I imagine thousands were saying precisely the same thing.

Imagine thousands of years ago, when they believed in golden calves and sacrificing children.

Imagine thousands of birds crammed into a dirty shed, only existing so their eggs can be taken and sold for profit.

Imagine thousands and thousands of Landsturm men moving about and plucking King Albert's face or the black, yellow and red from Belgian buttonholes!