Are very small departments necessarily sub-par?
If you're talking about MIT or Caltech, then the answer would be that their degrees in the humanities and social sciences are equally as respectable as those from any other colleges and universities in terms of graduate admissions (in social sciences/humanities).

Part of this is that we realize that folks who fall out of the mainstream at these schools merit some attention. It takes more of an effort and commitment to do sociology at MIT than it would at U-Michigan. For example, in order to get the credits to graduate, you've also undoubtedly taken courses in that discipline that were offered outside of that institution -- in MIT's case, you'd be taking classes at Harvard/Radcliffe. That takes dedication and forethought. 

Finally, we realize that students choose their undergraduate institutions based on limited knowledge and choice. We weight their accomplishments based on what they were able to do with the resources that they had.