There have been many reports of people being able to do this. However, the price is the same so other than the environmental factor, there is no advantage to doing it. Also, if the chip has been damaged by using the mug in the microwave or dishwasher, they cannot be reactivated. It's possible to get there and ask to have it reactivated and then find out the chip has been damaged and you'll have to buy a new mug anyway.
There's lots of information on the refillable mugs on this thread.
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