Why are EEPROM sizes measured in "k" or kbit and not kbyte or byte?
The marketing department got there first.  
Because they can.  
To some extent, knowing how many bits you can store has some value as EEPROM may be used for bit or nibble or ternary or Klingon-base-xxx storage. BUT most engineers can multiply by 8 and divide by whatever quite well so expressing it in bits has no vast value.


1 &amp; 2 can translate to "it sounds better and we may sell more". It doesn't and they won't, but hope dies eternal in the marketing department.

Some systems use other than 8 bit word widths so expressing in bits may make sense, but this is not usually a good enough reason. If you are using an Intersil 6601 CPU to build a DECMATE PDP-8 'compatible you may wish to use 12 bit words (but you'd be about 30 years late :-) ).  Otherwise using "bytes" where word size is 8 bits, or  "words" where word size &lt;> 8 bits, are just as useful or more so than bits.