Another thing to consider is 3rd party contracts. i.e. When your business outsources parts of your systems to yet another cloud provider, then your customers should be made aware such an arrangement exists, as that can in some cases make that 3rd party cloud provider a 3rd party data processor, depending on what data they have access to.
Disclaimer: I am not a lawyer but the above comes into play quite often in SaaS.
Because that's not how it works, they don't look at your cloud data like they do your browsing activities. It would be a show stopper for their businesses. Google at least has audit logs to show when/why their engineers were touching your cloud resources.