1.

They have more farmers, which many people do not consider to be an advantage.

think

They have more farmers, which many people do not THINK is (THINK of as) an advantage.

2.

Seventeen per cent of the mountain population works in primary occupations, in contrast to only 8 per cent of the total population.

whereas

Seventeen per cent of the mountain population works in primary occupations, WHEREAS only 8 per cent of the total population works in them (does so).

3.

They leave their wives and children to do the bulk of the farm work.

most

They leave their wives and children to do MOST of the farm work.

4.

Why should anyone resist any extension of the mountain economy?

point

What is the POINT of (anyone) resisting any extension of the mountain economy?

5.

The farmers contribute to the food supply.

contribution

The farmers make a CONTRIBUTION to the food supply.

6.

They represent the Switzerland of nostalgia and holiday dreams.

stand

They STAND for the Switzerland of nostalgia and holiday dreams.