#1: AM's, especially small AM's, continually have to fight the "nobody listens to AM radio" arguement. I usually use the "do you ever listen to NASCAR on the radio"? When they usually say yes (at least in our area) then I tell them they have listened to AM, specifically our AM, since we are the only NASCAR station within earshot. So far we have never heard "nobody listens to FM radio", at least yet! A translator magically makes that arguement dissapear!
#2 We have a pretty good signal (low dial, 1000 watts, tall tower) during the day, but at night our 18 watts barely gets to the city limits. Even our other station with 1000 watts fulltime, but high on the dial, gets eaten up at night anywhere outside of town. Any AM, and again mostly small AM's serving rural areas where we still can eke out an existance, who must reduce power or go directional, or both, looses a lot of audience. Consider Dec-Jan when sunset falls at 5:30pm! A translator just keeps on putting out that nice, round contour day and night, and in beautiful strereo.
So is a translator a magic bullet for AM's, I say YES!