When you put the stabilizers down, you don't take the weight off the axles. Stabilizers are not there to bear loads, but ensure it is stable. So if your TH is on stabilizers or not, the weight is on the axles, which is on the tires. With or without anything in it, nothing truly changes. I mean come on, my TH is like 9500lbs as it sits right now. You add 1100lbs as if it makes any real difference sitting.
Almost always trailer tires wear out from age before wear anyhow. Tires get old, crack, etc. Hard to drive enough in the period of time to have them wear out of tread.
Don't worry about it!
TH : 2016 Stealth WA2916
TV : 2012 Ford F-250 PSD