Frontier Airlines EarlyReturns (Pre-Alignment) - Can Frontier miles be credited to any FF program other than its own?

I usually fly Delta but for a trip later this month, I will be on Frontier. Can the miles for the flight be credited to any other FF program other than Frontier's own? In addition to Delta, I have American, Northwest, and Continental. I probably also have a US Air number, since I used to have an America West number, but don't know what it is.

I will be flying from DCA to DEN and from DEN to SLC. On the DCA-DEN itenerary, it says the flight will have a snack? What does "snack" mean in Frontier-speak?

I guess I have figured out that "Snack" = sun chips.

You can credit the trip to AirTran's A+ Rewards Program (http://www.aplusrewards.com/a_rewards_more_rewarding.aspx), I think that's it.