It does, its just that the sign up images are not needed, people can sign up on their PC, for the sake of 1.56MB flash they can anyway

Also Ive never actually seen where those images show on the XMB, maybe its only in different regions.
Trying to complete the info for the record... the images for netflix are...
Inside: dev_flash\vsh\resource\explore\netflix
ICON0.png
PIC0.png
PIC0_02.png
PIC0_03.png
PIC0_07.png
PIC1.png
PIC2.png
PIC2_02.png
PIC2_03.png
PIC2_07.png
Are the
http://www.psdevwiki.com/ps3/Content_Information_Files for a standard "HDD game"
Like the ones used by an standard .PKG is just sony took the weird decission of including them in the firmware
There are 2 groups of images that are displayed "optionally" (based on the language settings of the XMB)
- PIC0.png, PIC0_02.png, PIC0_03.png, and PIC0_07.png
- PIC2.png, PIC2_02.png, PIC2_03.png, and PIC2_07.png
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Lets use as example the first group for PIC0 (the other group works in the same way), PIC0.png, PIC0_02.png, PIC0_03.png, and PIC0_07.png
The images with a "0x" suffix are for languages (02=spanish, 03=french, and 07=portuguese) and only are displayed by XMB if the XMB is configured to that languages
Incase the image for the user language doesn't exists (as example for korean) what the XMB does is to load the "fallback image" from that group that is PIC0.png and uses english as default language (because there is no PIC0_09.PNG for korean)
This is the theory, so i think is 100% safe to delete the PIC0_02.png, PIC0_03.png, and PIC0_07.png (only keep PIC0.png) and PIC2_02.png, PIC2_03.png, and PIC2_07.png (only keep PIC2.png)
In resume, if you want to behave like the original (but "only in english") you only need 4 files in the folder:
ICON0.png
PIC0.png
PIC1.png
PIC2.png
-------------------------
A more drastic approach for the ripping is to delete all the images and keep only ICON0.PNG because this is the only image that is mandatory for a "HDD game" content (as stated in the SDK)
-------------------------
I never tested this myself though, and never installed netflix so not sure when are supposed to appear on screen, but i think that both methods i explained (remove only the language specific images... or... remove everything except the icon) should work
Edit:
Handy link with some firmware images --->
http://www.psdevwiki.com/ps3/User_talk:Eussbot