It is just some Telcos that price for data usage and put in usage caps. But this is only a way to price gauge customers. In the EU most ISPs operate without datacaps and are much cheaper month to month than in the US (my 1gb symmetric fiber connection without datacaps costs around 30 euro per month).

Sure a data connection in a datacenter is more expensive, but is either shared across datacenter customers or a customer gets their own. And again, global players have framework contracts with other global players.. so maybe Orange Business Services provides the internet connection for their DC operation globally.

The cost for the things they have to source locally is highly overestimated. Usually budgets they spend locally on stuff like advertising are much higher.