Being a sailor, Dogberry has had a lot of experience with people. Still, Lalafell kind of perplex him. He basically sees them as glorified moogles. That's not to say he wouldn't respect a showing a strength from one. It's just going to take a lot for Dogberry to realize that a Lalafell is a person just like he is. He might come off as condescending without realizing or meaning it.
No Gods and Precious Few Heroes