Goodyear Marathon Tire Load Limits

[MarkoPolo]

I have read a lot of threads on the forum that suggest Trailmanors will get "beat up" on rough roads with tires inflated to their maximum pressure. For my Marathon ST225/75R15s on my new 2922KD that would be 65psi.
The trailer dry weight is 2975 lbs with a sticker load capacity of 795 lbs which comes to a total weight of 3770 lbs. I will never travel with water in tank, grey water tank,toilet or water heater.
So, I can't imagine it ever weighing more than 5000 lbs, probably never much over 4000 lbs.
Looking at the Goodyear load limit chart, at 50psi, the max load is 4300 lbs, at 55psi it's 4440 lbs.
Would there be any reason not to keep pressure at 50psi?
I have seen some people keep a 12V air compressor to re-inflate their tires for paved roads. I would just as soon avoid that hassle if there is no particular downside to keeping tires at 50 to 55psi.
Mark