This bloke is a complete tool and a few sandwiches short of a picnic!
I had a B44 and the wheel nuts started coming off the nyloc was worn. I replaced them as thread lock was useless. My Durango nuts started working loose recently what did I do? Replace them. They were worn and guess what the thread lock didn't work either.
You say you are getting ripped off how? £1.69 for 10 nuts are you serious you complete moron. That is cheap as chips.
They come in large quanities for a reason. Buy new ones and sell it onto someone that has a clue and change your hobby.
As for the diff issue was more than likely your fault buy over tightening the gearbox cases nipping the bearings causing them to collapse.
Do you think there's a conspiracy against you? I doubt there is, I think you're just rubbish end of.