Tenderness isn't a problem so much, like I said we ride on a lot of rough ground so her hooves are pretty resilient.
Sure SC, but people whose horses are paddocked on soft ground - especially moist, soft ground - and who then go riding in rocky areas, especially with pointy rocks, and go at more than a walk or jog, often get sole bruising issues with their horses, and therefore quite sensibly boot them for such trails. In such scenarios, rough ground can lead to (avoidable) damage, rather than just toughening up hooves.
The kind that are meant for rocky trail riding are anywhere between $60-100+ for one, and a full set of shoes where I live is only about $55-$75. A full set of hoof boots would be the equivalent cost of 2-4 riding seasons of full shoes.
Plus they are only meant to last a few hundred miles, where I ride at least 20 miles each trail ride, so I would wear them out in about 1-1 1/2 trail riding seasons.
Now I really am confused. Say you pay $60 for a shoeing. Then your horse needs trimming and re-shoeing every 4-6 weeks - say 5, that makes it $600 a year for shoeing. Say you pay half that for trimming, if you don't trim yourself. You save $300 a year, which gets you a set of four new hoof boots, so that means you have parity even if your boots only last one season. Personally, mine have lasted three seasons and the shells are still good, I'm just replacing straps and wires.
Where I live we pay $100 for shoeing, and I can trim myself, so I'm way up with boots.