I think the only ones that don't get bonded have some reason their society would not want them to not breed. Marriages are arranged so everybody gets somebody. There are probably drugs, meditation techniques and V'shar style brainwashing to get the duds through the pon farr cycle. Or perhaps they just eunuch-ize them.
I'm going to assume that the LOTR program is organically developing according to events. Perhaps there is a timetable for programmed "random" events but these can be interrupted. For instance say the Uruk-hai are scheduled to descend upon a forest glade and slay everyone.. but if the living players in this holoprogram happened to kill that nest of Uruk-hai before this programmed event occurred it would not occur. While our Vulcan is only one person and not "playing" with any guidelines he will still interact in ways which change the environment, such as going pyscho during pon farr.
I was only suggesting banishment would make sense as a punitive measure chosen by elves, though I do recall some chose a kind of self-banishment in the books which involved departing across the sea never to return.