I don't know what is your basis for that claim. Looking at actual figures for different places where I live (Finland, which has many places with very good public transport options) shows that people who come by car spend substantially more money when they come shopping.

If that's true in Finland which I don't doubt I suggest that is a reflection of the very different built environment of that country compared to the USA. In the USA there have been several studies on the question and all have determined that arrival by car is associated with lower spending. Here is one:

http://kellyjclifton.com/Research/EconImpactsofBicycling/OTR...

Here is a roundup of numerous case studies. http://www.citylab.com/cityfixer/2015/03/the-complete-busine...

I think he got his first sentence backwards, his second sentence contradicts it.

People who arrive by car spend more than people who never arrive to that merchant.

I have no idea what part of the world you live, but near me cars are neither luxurious nor a burden to people. It seems like car angst could be a symptom of big city overcrowding. Overcrowding isn't a car problem. It's a problem of too many people in an area.