As pcrguy points out, there is high voltage at the ends of a dipole.
But, I've actually gotten away with using plain yellow nylon rope. I had a 40 meter dipole up for several years. The rope at the ends was supposed to be temporary while I tested it, but it worked OK rain or shine so it stayed as it was much longer than I anticipated.
Right now, all I have is an 80 meter inverted vee in place. I am using proper insulators between the ends of the antenna and the support ropes.