@Weltumschauung here's how you could create an account, buy lumens, and store them w/o handing over your private key:

1) Use the Account Creator tool to generate your public and private key. Save them somewhere safe, like a password vault.

2) Purchase lumens on an exchange and have the exchange send them to your public key.

3) From there, you can use the account viewer to send and receive lumens and check your balance.

The reason that you're seeing a focus on developers precisely because most people need apps/services/tools to interact with the protocol. We're focused on getting people to build localized tools to serve their own communities. We hope this encourages community ownership of the ecosystem, rather than a centralized ecosystem with Stellar.org at the center. Hope that makes sense.