.vmware_ha folder on non-heartbeat datastores

I'm noticing the .vmware_ha folder structure being created on datastores that are not configured as preferred HA heartbeat datastores.

Since this is a test environment I end up adding and removing datastores often. It appears every time I add a datastore it gets this folder. This in turn results in the error "vSphere HA agent on host 'x' failed to quiesce file activity on datastore" message every time I try to dismount the datastore.

Is there a reason this folder is being created on non-perferred datastores? Is there a way to prevent this? What is the correct procedure for removing it so I can cleanly remove my datastore?

Thanks!