There used to be flights, until recently, to Maota on the big island of Savai'i from the Apia city airport at Fagali'i. Since the Govt. closed this airport, I guess the short hop from APW or Faleolo to MXS or Maota just isn't worth it (30kms), the car ferry is very regular and travels virtually the same route.
The city airport at Fagali'i is still there. from what I understand, the villagers that own it have been at loggerheads with the Govt. for unilaterally closing it down. It was the preferred airport for travelers to American Samoa and made flights to MXS viable.
Watch this space. Polynesian Airlines is Govt. owned so won't have an opinion on it, but it would be to their advantage to have it open again as their DHT's can land at Fagali'i but the competition's Shorts SH6's (Air Samoa) and Dornier D.28's (Inter-Island Air) can't. And consumers want it open.