One big driver of the US not going to Chip and PIN is that it doesn't pay.
That is, they've done a cost-benefit study, and the costs (entirely new card readers, etc) outweigh the benefits (lowered but not eliminated fraud). They've also looked at how much friction there would be in the transaction if there was a chip/PIN involved - their nightmare would be even a small percentage of people paying with cash, or just as bad (worse for the merchant), skipping the purchase altogether.
They may be greedy, %_#)(_$)#(s and #_%)*$@&@, but as soon as the cost-benefit ratio moves in favor of switching, they will.
I do like the move of a lot of card readers to places where the user swipes - that will help quite a bit.
Overall, this practice of accepting some level of fraud used to bug the hell out of me, but since the user is (typically) not liable for fraudulent charges - the card-issuing companies are - I decided not to worry about it.
Also, this thread is dangerous altogether.