What the curiously-edited map doesn't show is that the western interchange is the exit for US 24 west to Colorado Springs, as well as a lot of businesses in Limon, while the eastern interchange serves US 287 traffic going in a completely different direction. Yeah, Limon has a third interchange not shown on the map that provides a shorter link to US 24 west of Limon. But you still need the overpasses carrying I-70 over I-70BL in the western interchange shown on the map, and it's not very expensive to add ramps to make that a simple diamond interchange for a speedier connection between downtown Limon and I-70.
Limon is a major watering hole, in a sparsely-populated (and boring) area of Colorado. Three cheap diamond interchanges for Limon is not excessive.