Profile: 7a56f8bd...

Not sure if this is still a thing but there used to be 'key exchange parties' where people can meet in person to exchange their public keys

You can upload a selfie with your pubkey written down on a piece of paper or link your key on your other social media accounts like twitter, instagram or whatever

Phoenix doesn't take a cut if you send from LN to a bitcoin address, the fees depends on the bitcoin mempool usage and their current UTXO rate. All fees go to the miners.