Folders disk1, disk2, disk3 - stil exists

Hello,

I put a few usb flashdrive to my mikrotik, and Mikrotik created folders for that flasdrives named

disk1
disk2
disk3

I noticed that the folders still exists, even if I remove and reboot the router.
After reboot that folders are alway created, but please notice that I do not have any usb flashdrive inserted:

[admin@Mikrotik] > /disk print 
 # NAME                            LABEL                            TYPE    DISK                                  FREE       SIZE

[admin@Mikrotik] > /file print 
 # NAME                                            TYPE                                                 SIZE CREATION-TIME       
 0 flash                                           disk                                                      jan/01/1970 01:00:00
 1 disk1                                           disk                                                      jan/01/1970 01:00:02
 2 disk2                                           disk                                                      jan/01/1970 01:00:02
 3 disk3                                           disk                                                      jan/01/1970 01:00:02

When I remove it is OK:

[admin@Mikrotik] > /file remove disk1 
[admin@Mikrotik] > /file remove disk2 
[admin@Mikrotik] > /file remove disk3
[admin@Mikrotik] > 
[admin@Mikrotik] > /file print        
 # NAME                                            TYPE                                                 SIZE CREATION-TIME       
 0 flash                                           disk                                                      jan/01/1970 01:00:00

But after reboot I see that folders are created:

[admin@Mikrotik] > /system reboot    
Reboot, yes? [y/N]: 
y
system will reboot shortly

And after reboot I see:

[admin@Mikrotik] > /disk print        
 # NAME                                  LABEL                                  TYPE    DISK                                        FREE       SIZE
[admin@Mikrotik] > /file print       
 # NAME                                                     TYPE                                                          SIZE CREATION-TIME       
 0 flash                                                    disk                                                               jan/01/1970 01:00:00
 1 disk1                                                    disk                                                               jan/01/1970 01:00:02
 2 disk2                                                    disk                                                               jan/01/1970 01:00:02
 3 disk3                                                    disk                                                               jan/01/1970 01:00:02

That is normal?
How can I remove that folders completely?


BTW, I noticed bug that when I put some on usb flasdrive to Mikrotik, when mentioned folders are created that this flashdrive will not be mounted till I remove manually that folder.
Does it normal too?

Same problem on RB3011.

Found a temporal solution for this issue
http://forum.mikrotik.com/t/both-old-and-new-disk-names-are-showing-in-file-list/117217/2