My issue is that does Monsanto still have the right to do that if they in fact wanted to?
Farmers like this product, that is why they buy this product. This product is expensive so some seek to find a way of growing this product without paying the price.
Growing a different strain nearby is no way of getting reliable transfer of the GM crop to your non-GM crop - and so far (despite this being a very popular story) nobody who Monsanto has gone after for IP piracy has done this - nor would Monsanto have much of a case if it did happen this way.
I suppose they could if they really wanted to.