The two scenes may not be directly linked in the plot, but as RealityChuck points out, their structure and theme are very similar. The scene with Mike foreshadows the subsequent scene with Jerry.
Think about Of Mice and Men. Early in the story, the old man's dog is so old and sick that it needs to be put down for its own sake. The old man lets one of the ranch hands take the dog out and shoot it. This sets up the pivotal final scene in the book and movie, which has a very similar structure and theme, but with much greater consequences.
The same thing is happening in Fargo. The scene with Mike, which is relatively innocuous, helps to give the scene with Jerry that follows, which has much more serious consequences, more power.
It's also a motif of the movie: Interviews that conlude in unexpected ways.