In these early days of a new blockchain with many people moving from one blockchain to another and the software and servers behind the new blockchain settling down and working out the kinks, I think it's important to take a moment to discuss what an airdrop actually is.
Listening to some in the community, it seems there are many things people think an airdrop is, or what it represents.
Essentially, an airdrop is a gift. When you receive an airdrop it doesn't remove or invalidate any other tokens you have of whatever type, it simply gives you new tokens in addition to what you already have.
For example, in the current situation of people coming from Steem and getting airdrops in Hive tokens, it works something like this: Imagine you have a pocket full of American dollars and decide to take a trip to England. When you get there, they give you a number of British pounds equal to the amount of American dollars you have. If you have five dollars, they give you five pounds. But, even though they gave you five pounds, you still get to keep your five dollars on top of that. It's not because you earned the British pounds or exchanged your dollars for them, it's just because they decided to give it to you as a gift.
That's essentially how this situation is working as well. If you have Steem and as a result were given an equal number of Hive tokens as an airdrop, that's a gift from the new blockchain. It doesn't effect the amount of Steem you have on the other blockchain... you still have the same amount as you did before. Whether you receive an airdrop of Hive tokens or not, you can still use the new blockchain to start earning the new tokens.