If you want to have your #sats in your own custody, you have to open a channel - a smart contract on #Bitcoin main chain.

There are fully custodial wallets where you don't have to open any channels like Wallet of Satoshi but in that case, you don't own your #sats, the wallet provider does hold it in their channel. It's OK for small amounts like less than a million sats or something, I guess. Most people use them here for zapping.  

 I think a fully custodial wallet is what I want.  Where I can transfer a small amount of BTC (which is self-custody) for zapping and receiving zaps.  How does the wallet provider make money?  Do they take a percentage? 

 They take small fees from the transactions and some sell other services like swapping between on-chain and LN. We are so early, many operators are first building the solutions and care about earnings later.