On several different occasions, someone has ranted on how their neighbor cuts/mows his or her lawn late, disturbing the peace of others. All I can say or add is that perhaps you should just be happy that they keep their lawn up and keep the grass cut. Imagine having a neighbor who lives in a nice neighborhood or tract, and who doesn't seem to think that his lawn needs to be mowed? It's not only unsightly, but it speaks volumes as to what type of people live there, also. So, look on the bright side of things and be happy that they keep their lawn up!