There are a number of reasons why we do not do this, which largely comes down to cost versus benefit. There would be the initial outlay required for the bags and hanging stations. There would then be a maintenance overhead on the green keepers to ensure that bags are filled. If a seed mix were to be used a further overhead would occur on wet days as the bags would need to be emptied to prevent germination of the seed. There is a high likelihood of a proportion of bags getting inadvertently left out on the course, which again would require someone to go out to find and recover them. Also, the golfers who do not currently bother to repair divots on tees, replace divots on fairways or repair pitch marks on greens are highly unlikely to bother to use the bags.