Why do I get multiple instances of the same scanner?

[alloydog]

Why do I get multiple instances of the same device and how can I hide them?

The various scanner applications (XSANE, Simple scan, GIMP and so on), all show half a dozen or so "different" devices, when in reality there is only one.  Also, not all "devices" work.

For example, if I use Simple Scan, it gives me the following devices to select from:
EPSON ET-2720 Series:002:007
EPSON network scanner
EPSON PID
ESCL EPSON ET-2720 Series
ESCL EPSON ET-2720 Series SSL
ESCL EPSON ET-2720 Series [5839454A3039313612]

However, only the ones with ESCL in the name work.

Then, when I use GIMP, which calls up XSANE, it again lists them, but with slightly different names:
[i]EPSON ET-2720 Series:0 flatbed scanner [epsonscan2:ET-2720 Series:002:006:esci2:usb:ES018F:4439]
EPSON network scanner flatbed scanner [epsonscan2:networkscanner:esci2:network:192.168.0.130]
EPSON PID flatbed scanner [epson2:net192.168.1.130]
ESCL EPSON ET-2720 Series Se flatbed scanner [escel:https://192.168.1.130:443]
ESCL EPSON ET-2720 Series Se flatbed scanner [escel:http://192.168.1.130:443]
ESCL EPSON ET-2720 Series [flatbed scanner [escel:http://127.0.0.1:60000]

1.  Why is the same device listed in six(twelve) different way?

2.  How can I remove/hide the non-working options?