Interesting. They must be expecting some pretty light flights during the next few weeks. I'm sure the overcapacity on the LAX route is a contributing factor for that route. I did a spot check for a trip MKE-LAX from 2/4 to 2/9 and it's $102 outbound and $69 coming back. Interestingly, the $69 fare said it was a fully refundable fare.
AirTran on the same dates is offering two outbound nonstop flights for $99 and $89 for the return.
In total, YX and FL are offering a combined 3x day from MKE-LAX, which has to be overkill in February. I am flying that route in less than a week, so I'll report back anecdotally on what the loads are like.