I have a few questions about paper wallets. Firstly why do you have to transfer all your Bitcoin out of a paper wallet or risk losing the *change" I don't understand that.
When you generate a well secure paper wallet, your private keys haven't toucher anything connected to the internet. This means that your coins are 100% isolated from anywhere that may be infected with malwares. That's why a paper wallet is a good option for long term storages.
When you want to "cash out" the coins from your paper wallet, you will normally import your private key in a device with internet access. Now the private key isn't isolated anymore, so there is always a risk of having your paper wallet data stolen by someone. That's why people always tend to generate a one-use paper wallet, that is disposable after its use.
Next is the real reason for posting this and that is do I get airdrops such as BCC if my coins are in a paper wallet ?
BCC wasn't an airdrop. It was a fork from the Bitcoin network.
Imagine that you send 1 BTC to your paper wallet. The blockchain has this transaction recorded as X sent 1 BTC to Y wallet. This means that for every one in the network, this specific address Y contains 1 BTC.
When the Bitcoin Cash chain was created, it took the same blockchain from Bitcoin and continued as a different coin in a different path. Since your 1 BTC where registered in this specific address, and Bitcoin Cash started using the same Blockchain as the legacy Bitcoin, you have the same amount on both sides of the chain.