They are actually very good for that. I've seen folks use lots of vine type plants as ground cover... pumpkins, squash, melons, even cukes. Just sometimes it's unplanned such as when you give refuse from those type plants/fruits to pigs and other livestock.
Those "unplanned" plants are always a nice surprise to see! @Bruce maybe you should "nonchalantly" throw some watermelons out to feed the birds or your chuck friends, perhaps you might get some watermelons
I missed it if you mentioned it but do the sheep like watermelon vines?
Mine are picky and won't eat much out of the garden. The rams though will eat just about anything. Ringo will come galloping when he sees me carrying an ear of fresh corn. I originally broke them up to keep him from choking but he chews it up cob and all.