Loading railcars

[farmaholic]

Have you, or do you know of anyone, who has
loaded railcars out of privately owned elevators
that had it written into the purchase contracts that
it wasn't allowed?

Some of the original sellers of these facilities aren't
even in business anymore or you could say
morphed into something else. Or the original
purchaser has sold it. Or maybe it's changed
hands several times since the original sale. I've
never seen a contract, but does the wording allow
for that term of the contract to apply to the sale
and resale of facility into perpetuity? Has anyone
challenged this?