Mark,
I see it most everywhere!
Remember all that you heard about the Dutch Elm Disease. Well, it was then that the "back-up" tree arrived. Truly, the American elm was a beautiful hardwood with unobtrusive root zones and high canopies.....When located in the proper places, it was a nice golf course tree if there ever was one...... As it perished, awareness of attrition escalated and the practice of planting "replacement trees" became the rage. However, with sensitivities high, as a safety measure, a countless number of "back-up trees" were also planted in close proximity to healthy ones "in case" they too perished.
The problem has always been that these substitutes were cheap golf course varieties. Debris-ridden conifers and evergreens, such as white pines, hemlocks, cedars and spruces, were typical poor choices. These varieties not only possess shallow root zones which are a maintenance burden, but they also manifest low extending limbs which restrict the swing, obstruct recovery play, and cause unhealthy summer turf and winterkill.