little steps can have a big impact

When people talk about their impact on the environment, it's obvious when they 'get it' but just as obvious when they bury their heads in the sand.

Those in the former camp know that if everyone does their little bit collectively, it can have a massive impact on the wider issue. Those in the latter camp only see the little bits in isolation and struggle to see what difference such a small change can have.

There are similarities to how bus travel is sold.

Some operators expect potential customers to ditch their car (that cost them thousands to buy, and hundreds to tax, MOT, and insure each year) per se and take the bus for every journey.

Others see the more realistic, bigger picture. 

They know that if lots of people swap just one car journey for a bus journey each month it would have a massive impact on the success of their business. And it's the easier sell too.

Something that would fundamentally impact their travel plans long-term against something they would hardly notice (from a behaviour or financial perspective).

Break it down into bite-sized chunks and people are more likely to do their little bit, perhaps without even noticing it.