Sure it's essentially the same thing...the only difference is scale.

Frontier wants to fly nonstop to the east coast because:
(a) traffic levels exists to support it
(b) a connecting DEN-east coast flight is not very competitive versus other airline nonstops
(c) feeder traffic into the DEN hub would have to double-connect to get to the east coast in markets such as BOI-LGA.

For these same reasons Midwest wants to fly nonstop to the west coast. The link with Frontier doesn't really change that.