I don't quite understand the excuse that it is not offensive in the USA, -surely its usage has the same origins as its usage as an insult in the UK. And therefore it is intrinsically offensive, I think some heads may roll at Hasbro - it wouldn't have taken much research or common sense to find out how offensive it is.
I come from a generation where this word was used in a medically descriptive way. My brother had CP, and was referred to as a spastic by doctors, and by my parents who cared for him (I'm talking 50's and 60's), because it was considered the appropriate term, and referred to the rigidity of his muscles, and his involuntary movements. But during my childhood it started to be used offensively as an insult, which was very unpleasant for families like ours, where a beloved family member had CP.