Using gomo in the USA

But hardly for the 30day rolling contract for life gomo cost of 9.99E/month including calls,sms and 30G data in EU ?
 
But hardly for the 30day rolling contract for life gomo cost of 9.99E/month including calls,sms and 30G data in EU ?
I was thinking as an add on, you still pay your normal monthly sub but if your going to USA or some where outside of Europe for 2 to 4 weeks you buy an additional allowance to cover this from your provider, it just seems in this day an age that you shouldn't have to use a third party for this