Here in Norway we have cured pork belly for hundreds of years without any trace of nitrites/nitrates, and I'm quite sure other countries/cultures have some of the same traditions, as well.
In fact, pink salt has been banned from foods for several years, before EU regulations made it legal to add a small amount.
Pink salt does have it advantages, the structure of the finished product is a bit different, as well as the colour, and taste, and as before mentioned, the fat is fresh longer before it gets a rancid taste.
We have two kinds of pork belly, bacon, which is lighty cold smoked, and "flesk", which is just cured and not smoked at all. Both types are made with regular salt, and can be kept in the fridge for a month or two. It helps to keep it dry, and in an airtight container in the fridge.