It depends ... slide in spacers of about half an inch or so that just go between the wheel and the hub, if built correctly, add negligable stress to the hub assembly.
Anything bigger than that, especially 2", requires spacers with adapter lugs and is considered a big no no because it adds too much stress on components ... especially if the vehicle is driven aggressively and off road.
You will read around many forums the usual 'I have run them for years with no issues' ... but this is the kind of thing that all seems good until something brakes and a wheel comes off at 70mph.
After much research I ran 5/8" slide in rear spacers on both my hoe and my yuk ... personally I would strongly recommend against 2" spacers.
That much spacing is much better and safely achieved through wheel offset than spacers.