I know of several clubs in the Grand Rapids, Mi. area who lost fields due to encroachment. One field was supposed to be leased to a club in perpetuity but after the owner who was also a flyer, died, his widow remarried and the new husband kicked the club out and made the area into a mini golf course.
Our club, The Charlevoix Area BUFFS own the property we fly on. However a parcel of land adjacent to the north end of our field was sold and the new owner keeps horses there. So far everything has been cool and calm, but I'm afraid it's just a matter of time before the little hobby rancher gets her dander up and raises a stink. Don't think she could do anything to stop us though.