Utterly stupid.
No need at all for Sim cards in todays era.
How do you switch to a cheap payg sim in another country for cheap rates without a sim ?
When you load up your phone in that country, you connect via any provider you wish via an App on the phone which scans the networks available to you, for you to select your operator. This can be pre paid and loaded via the web if you wish, or can be purchased via the App account on the phone, for data, minutes, messages etc. And registered to one phone at a time, this would allow for multi switching of multiple network accounts as the phones IMEI is registered to the network.
Simple