I just saw a contract for a summer camp and... wow, is this even legal? Check out this part
Staff Member shall not offer, solicit, or induce, either directly or indirectly, verbally, in writing or by any electronic transmission, including, but not limited to, texting, email, social networking, any of the campers, other employees or patrons of Employer for a period of three years after termination of this Agreement. This shall include, but not be limited to, encouraging campers or other employees to attend another camp, whether day or residential, or any other program, including any travel or teen tour program offered during the months of June, July or August.