For exchanging this cypto-currency to local or international currency we need different system like PayPal and others service providers.
Honestly some people really got their bitcoin just by doing some bitcoin related works and because they are used to it for many years, they are now able to accumulate a decent number of it since they started. Because at some point that people doesn't want to buy bitcoin, they used to work for it instead and the result is quite as no doubt we have lots of options and method on how to get bitcoin without harming our own fiat pocket.
There are number of ways on how to earn bitcoin, like what this user said above, many would actually prefer working to earn it rather than shelling hard earned money just to buy bitcoin. one can join signature campaigns, facebook campaigns , telegram , et al. but companies starting campaigns will just give you tokens of their own and you would wait for it to be exchanged into bitcoin.
But if you want, you can buy precious bitcoin now while it is still in a state of low value. shopping spree right? more bitcoin for lesser price..