I will give this as the first part of my information, I own miniatures and we show them, so therfore the rules state no shoes and no nail holes from having shoes on the horse or a disqualification and a ban from the AMHR is a result. We jump, drive, race, and trail drive these miniatures with no problems. If you have a good hoof to start with, why add shoes? Once the hoof forms its callus your horse should have no problem walking on hard ground. This is of course as long as there are no hoof problems. Even with the two full size horses I had that we trail rode all the time, I would only have shoes put on them if they were going to a local state park around here during the muddy season because the rocky ground would slide out from under them without shoes. When they had shoes on they had a better grip and did not slide around as much when we rode there. The rest of the year I rode with no shoes on any of my horses there and I had so many people who were like "oh no, you are riding without shoes here, you are going to have a sore or injured horse tomorrow!" I did it for years and never once had a problem. We even went on 3 and 4 days rides there and never once came up with a lame horse. I still own the one trail horse and she has not had shoes on now for 3 years and she has done just great. I have not trail rode much lately, just a lot of walking the roads and local nature preserve by my house.
My point is unless you are doing a lot of riding in wet, mucky ground or riding the cliffs up and down, then why ruin a good hoof with shoes?