[Q] What's with all these mnt_1, data_1, data_2, data_3 topic

Have been using exclusively mrRobinson's method (ODIN + pre-rooted images) ever since I got my S3. Have not paid close attention until recently, when I noticed the many empty folders with the _x (x = 1, 2, 3, etc...). Any idea if I could just get rid of them?

And a related question: if I would like to start "clean" with the next new image mrRobinson may release any time now, knowing that I have all my data backed up, what would be the best way to go after it? Wipe data/factory reset, prior to ODIN-ing the new? Else?

TIA