I don't see why you should. In fact it might even cost you more to do so, if they charge you for going through an international exchange. [...]
That's what I guess too.
Nope, in general. As the name suggests those numbers are for international calls. On very rare occasions it also might be cheaper to make an international than domestic call when one select between operators in neighbouring countries.
There were cases back in time when operators didn't necessarily have comprehensive roaming deals that a call from country A was 1st routed to your operator in country B after which the 'call' started back to A. This took time & the cost were astronomical and if there where no country code the call probably didn't connect anywhere. I still save all numbers with the country code.
G
Thanks
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