OBV less strict about topic drift here than "Pictures that made you LOL" I reckon (many, not all) folk like students who are buying "what's the cheapest vodka you've got" are just recognising that once you've added the too watery or too syrupy coke and glassful of ice there really isn't much nuances left to appreciate in taste even if you were interested. And of course, even if you only need four or five voddies to get the gumption up to dance in front of people or talk to interesting strangers in a club; buying them at a quid a go rather than 2.60 is a fair saving. That difference can mean affording a good enough cheap night out (club entry, alcohol to loosen up & chill out, maybe taxi home) or staying in watching TV. (Yes, lots of folk in the UK do go out to get drunk as they can, but it's good to mention the other side & not tar all!)