We're both from Europe, maybe it's a millennial thing. We both lived with flatmates before moving in together, so we just continued splitting expenses like we w

We're both from Europe, maybe it's a millennial thing. We both lived with flatmates before moving in together, so we just continued splitting expenses like we were previously doing with flatmates. It happened naturally and seemed logical at the time. Fast forward a decade and we still do it this way. We must be doing something right because we never argue over money or similar topics. Why change something that works?