To step back a level of consideration: if you're already running on an IaaS platform that has its own (expensive) object storage, can it ever be worth it to run

To step back a level of consideration: if you're already running on an IaaS platform that has its own (expensive) object storage, can it ever be worth it to run your own object-storage system using that same IaaS provider's (expensive) compute? Or to run your object-storage system on some other bare-metal host, and then PUT things into it using your IaaS provider's (expensive) egress bandwidth?