This argument has the same line of reasoning that the businesses originally tried to use when the city did put in buffered bike lines - that removing unfettered automobile / truck access was the death knell to commerce

(Like these: http://gothamist.com/2011/07/14/post_blames_bike_lanes_for_b... http://www.villagevoice.com/news/new-east-village-bike-lanes...).

In the case of the bike lanes, this is the furthest from the truth (have a Google for lots of arguments about the merit of increased bike traffic).

I'm not sure what the solution is, but there certainly is one that would support a few car/truck free avenues.