Sometimes I get free accommodation (recently that included a stay at the Intercontinental, two meal vouchers, transfers, and a city tour when flying economy class on LAN from AKL-BOG with a stop in SCL) when in transit involuntarily (i.e. there is no flight leaving on the same day to my final destination, and sometimes I don't (e.g. when flying business class on SQ on a RTW).

Are there any rules that determine this? Is there ever a situation where you are entitled to it?