It is common for large customers with multiple clusters to use Resource Pool to organise their VMs. The reason is the VM folder spans across clusters. The folder is at the datacenter level. The screenshot below (vCenter 5.5) shows the folder. I use folders a lot. A limitation here is I cannot filter them by cluster. The Datacenter actually has 2 clusters. That’s not visible here.
vSphere web client makes it a little easier. It still does not have the folder structure. This means I cannot see a folder hierarchy (parent folder, child folder). However, I can now show my VM by cluster. In addition, I can filter the list, as can be seen on the right.
As a bonus, you see that under “Related Objects”, there are objects beyond VM. This means I can list other objects. For example, I can choose datastore. The filter on the right changes accordingly.
I think the Filter features are very useful in large environment. Cool!