Balanced tires...

I'm normally a stickler for detail. I had a trailer tire repaired once and a new one mounted once at this particular local tire place. Both times they casually said that they normally don't do it, you don't feel it and they don't need it! I insisted, and they did.

Well, of course you don't feel it because it's on the trailer. But you would normally feel it in the vehicle you are sitting in. If anything can be felt, it means that it's not rolling as smoothly as it should. Any "imbalance" WILL cause some degree of irregular wear and undesirable harmonics, vibrations & loads on the wheel bearings & suspension. You can get by with it, just like with a factory engine balance job. It's "close enough". But if you want it, in my opinion, "done properly", balance them.

Over time, even balanced tires may wear unevenly enough to change the balance - regular tires or slicks, even if you don't feel anything. I've seriously considered it, but just never got around to rebalancing them part way through their life.