Sadly...
... there are a million and one reasons why people hate involving IT, starting with "change requests that take 30 days to fulfill even though it is a five minute change" to "bad attitudes and 'RTFM'".
I worked at one company (think top 5 global pharmaceutical companies) where the Facilities department (the lights and toilet paper people) actually made their own IT department under corporate radar, with their own servers and staff just because corporate IT was such a royal pain to work with!
I think that is one reason why we see the split, too.
J.Ja