I've contacted the support about this, and here are the answer received:
That is expected behavior, if you uncheck Quiesce Guest File System and Application and Applications, a crash consistent hardware snapshot will be created instead.
From the documentation:
Consider the following before enabling or disabling the quiescing during the backup:
Hardware Snapshot with Quiescing - When you perform the SnapProtect backup of a subclient, a hardware snapshot of all the virtual machines is created. Before the snapshot creation, the quiescing will be performed automatically for the operating system and applications on all the virtual machines in the subclient.
Crash consistent hardware snapshot - The backup process may slow down because of the quiescing. If you do not want to perform quiescing before the snapshot creation, you can disable the quiescing. If you disable the quiescing, the crash consistent hardware snapshot will be created.
The only difference between the two options is the lack of application/Operating system level quiescing if you diable the quiescing.
You cannot disable the snapshot as that is the basis for the backup of VM’s.
So, I think this answers the question, you cannot disabled VMware snapshots.