6 on the ground one spare
you prang a tyre swinging wide to get around a tree on a winding bush track (this happens with trailers)
Now you have 6 on the ground and your spare has a gash in the side wall no plugs or patch will help that.
Sure you can just make it to the next town ... ... ... or not :)
The feeling of having a second spare is priceless when you are say two days drive from a service location and the above happens. Perhaps consider carrying just a spare carcass on the trailer, you could stuff the inside to maximise space and save on weight.
Two spares when towing is kinda important in my mind
s

