teaching - What is the role of research in liberal arts college faculty evaluation?

Lately, I've been wondering why institutions with a primary emphasis on undergraduate education (e.g. liberal arts colleges) value research output amongst their faculty. This is not intended to dismiss the research of LAC faculty, but rather to delineate what value the institution/department gains by hiring candidates with superior research output, perhaps at the expense of someone with a stronger teaching record. Here are several reasons I have heard, arranged in reverse order (approximately) of direct student benefit:

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  Current faculty wish to promote research in the discipline for its own sake, without regard educational benefits for the students

  
  


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  Tradition, or emulation of more prestigious institutions.

  
  


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  Faculty need a strong enough research output to get tenure (a somewhat circular reason)

  
  


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  Reputation within the research community enhances departmental and institutional prestige, with incumbent benefits for students.

  
  
  


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  The faculty can extend their academic network to their students. Examples of this might include increased regard for letters of recommendation and awareness of (non-)academic opportunities.

  
  


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  Research output is a proxy for breadth of knowledge within the discipline, hence for value of content in instruction, both formal (course syllabi) and informal (answering that random question during office hours).

  
  


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  Research output corresponds to the baseline knowledge needed to supervise undergraduate research and teach best practices.

  
  



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  Research activity is the best way to keep faculty aware of changing trends in the field, which in turn gets incorporated into educational practices. After all, academic careers last a long time.

  
  

I'm sure there are many valid reasons missing from this list, including some of the most important. I would like to know from a institutional/hiring perspective:

a) What reasons for valuing research activity are missing from this list?

b) What benefits are weighted most heavily? Which are given little or no thought?

c) To what extent are these benefits distinct from the ways that research profiles are evaluated by hiring committees?