It's a common confusion, but when you contract with Google Cloud, the service is provided by "Google Cloud EMEA Limited, Ireland", which is an European company, and when they provide you with a datacenter in Europe they are totally an European company operating in Europe.

This is different for example to DigitalOcean LLC, that is a US-entity providing service to European customers (this example has to be verified, but that's what I remember).

It can be an extra layer of security. At some point in the future there will probably be another exploit in supervisors or hardware that can be used to spy on other tenants. With dedicated servers that becomes harder.

I've heard of large companies that require their own hosts. But then again, if you're big enough it really makes sense to build your private cloud anyway.