I have the snapshot function linked to manual saving too.
And I end up with a lot of snapshots.
Which is fine by me: better too much than not enough when you need it. 
Every now and then (between significant steps of my creation process), I do a special backup that I identify being purposed as a âsnapshots backupâ.
Then I just ditch all but the last one or two snapshots from all documents within my project.