What you plant, when you plant, how you plant and especially what your desires are for your ground is a deciding factor in planting anything.
Farmers want to keep to soil as good as possible for their planned crops to be used for sale. A cover crop of what they choose has to do with their needs to produce the best tonnage for sale. A casual gardener will often have entirely different desires. And a person who desires a green grass yard may not want anything "invasive" to his preferred appearance. Then you have the folks who want something specific for wildlife.
ALL kinds of various desires & needs.
I like clover. I use it to help keep the deer in my area. And for my yard,, as long as it's green colored, and keep the soil from washing away,, I could care less about what grows. Function over appearance.