Far from being a trivial issue, this is probably one of the main reasons bitcoin will not be able to serve as a world currency. We had thousands of years of gold and silver backed money with no real mechanism for creating money through lending, literally out of thin air. But that's also why for thousands of years we had only petty economic growth and development. Our ability to create money as well lend and borrow against the future is what's allowed the phenomenal economic output of the past century or so. Any currency that is deflationary and does not allow for this will probably send us back in time. We've been there. We know it doesn't work well. It's good to have the option, though. And I guess bitcoin will become much like gold, a scarce resource that will allow us to protect our wealth against inflation but, at the same time, use it to pay for goods and services. Mind you, also because of blockchain technology, gold is being digitised and heading in that direction too!