While others are asking "Why is CompanyA buying a /48 a week?", my question is "Why isn't ISP-A asking CompanyA why they need a /48 a week?"
IPv6 operates in several of these hierarchical subnets. A /64 is the smallest, and is usually for customers and edges. A /48 or /52 is reasonable for a datacenter, as it provides up to 2^12 subnets.
But even then, doing a /48 per DC, there is no reason for not-Huge-Cloud-Provider to be gathering that much IP.
This may actually be a situation the market can take care of: If you're an ISP that is hooking up spammers with a new /48 each week, that starts to reflect poorly on your /40.
IPv6 operates in several of these hierarchical subnets. A /64 is the smallest, and is usually for customers and edges. A /48 or /52 is reasonable for a datacenter, as it provides up to 2^12 subnets.
But even then, doing a /48 per DC, there is no reason for not-Huge-Cloud-Provider to be gathering that much IP.