Yes, 2 seperate incidents, without going into too much detail, i allowed a club usage of files to print in their program but later found they were selling 7x5 inch prints from these files over a 2 year period, i sued for over £2500
second case was another club using paid for files in ways which weren't pre agreed, ie they used them in promotional and advertising material without asking as per the original terms of usage didn't allow this usage. didnt take any action other than to sever links and issue a threat to take legal action unless they destroyed all previously supplied images.