All I know is what several of my friends in school told me about as they prepared to get their BSs in horticultural design. They were told emphatically that fruit bearing trees were "not suitable" for urban design because they were "messy and stained the sidewalks and pavement". Therefore, I think that is why we have lots of non-fruitbearing Bradford pears and Japanese cherries used in towns and cities across the US.

Even if the fruit from these trees was not harvested, we would end up feeding a lot of wildlife. As usual, local governments talk "green" but are really anything but. This attitude could be easily overcome with just a trendy "style change" aimed towards ag universities and city governments.