Consider this: The incentive for the banks in using chip and pin cards is that they are supposed to be near impossible to clone, and thus there is a "liability inversion": Unlike with mag-stripe + signature cards, with EMV cards, the assumption is that if the pin was used, the customer is liable. With some exceptions.

Couple that with massively reduced fraud.

Now, if they allow a method for cloning these cards, both of those go out the window: Criminals will just attack the weakest point, which is going to be whatever mechanism Coin would use to allow cards to get added to their device.

As for the US market: Consider that pretty much all large US banks have committed to start rolling out EMV cards (though many will roll out chip + signature rather than chip + pin, which seems the height of stupidity)