Consider the case of a small national telco that happens to have a large number of incoming tourists.
There's an additional burden on their network, and they should be able to recoup some of that cost.
But almost every carrier I've seen would charge extortionate rates - hundreds or thousands of times the price they would charge their local customers for.
Small telcos rarely handle these things themselves and instead resell bigger telcos. If anything, I hope this triggers an investment in optimising this infrastructure; if i can use the internet without caring where the physical servers are, so should my phone be.
Recouping costs is different from charge through the nose for international traffic.
Yesterday, that traffic typically was priced at euros per _mega_byte, starting at the first bit transferred; starting today that's at most €7.70 + VAT per _giga_byte, starting after you have used your (fairly generous) fair use allotment, going down to €2,50 per gigabyte in the coming years.
Naturally, countries who see many tourists heavily opposed this change and lobbied to keep the maximum price that the EU now has set high.
There's an additional burden on their network, and they should be able to recoup some of that cost.
But almost every carrier I've seen would charge extortionate rates - hundreds or thousands of times the price they would charge their local customers for.