Amazon doesn't really argue the green case very well.
It's not that everybody should get on their bikes...it's that those who can should.
IF you're doing a quick essentials shop, IF what you're getting can fit in a rucksack, IF you live close enough to cycle there (by your own standards - nobody elses) then it would make sense to get some fresh air and bike to the supermarket.
It's not about getting everyone on their bike regardless of circumstance.... or trying to find loopholes in that circumstance... it's just that, if everybody who COULD cycle DID cycle, or could walk did walk, then the world would be a greener place and the local traffic congestion around Marple would - probably - be less of a pain in the bottom.