All those "minute contributions" to global warming add up to a catastrophic problem. If all those (genuinely) rural people in developing countries start adding their "minute contributions", heaven help us.
Rural motorists impose other substantial costs, in noise and in danger and unpleasantness. Many country lanes that 30 years ago had negligible traffic have become de-ruralised roads with several cars speeding past every minute. Children can no longer wander free and lonely but instead, to quote your letter-writer, "two cars are essential ... for ... the social lives of our young children".
The priceless qualities of the countryside, its tranquillity and freedom from unrural sounds, are eroded by motorists in rural areas. They must be heavily taxed accordingly.
ROBERT P CLARKE