It's not a scheme. And I would advise anyone who asked to make up their own mind about where to store it. If they feel confident that they can 100% keep their wallets safe better than CoinBase can, then absolutely, yes, they should keep it on their home machine.

The promise of BitCoin is that it functions like cash, with all the advantages of electronic payments. If I can't bring my cash with me everywhere, then yes, it does fundamentally limit its utility to me.

BitCoin is just like any other money: the base system is based on distrust but for it to be mainstream an ecosystem of trust must be built around it. If we can't sort out the difference between competent BitCoin institutions and incompetent ones then we are in a world of trouble.