wellygary: Such stupidity don't seem to stop NZ post, So I suspect this is not an actual OSH restriction, just that they have contracted a bunch of lazy a$$ed paper delivery people who only drive round in cars......
It would boil down time vs money. If you have to stop - and perhaps find somewhere to actually park - then walk.....to whatever box or (other) that may be there....the time taken per house may - on average - increase by a significant amount.
It may not be that the delivery people are "lazy"...it may be more fair to say they aren't being paid for the additional effort (and time) required.