If it's a chippy worthy of the name, then a good old-fashioned haddock and chips is the food of the gods.
I'm not sure anything from a chip shop counts as a snack, but in the spirit of the thread, I'm going to have to go for chips, served inna cone with a little wooden fork, unadulterated apart from a sensible (as opposed to chucked on with a trowel by the chipshop owner) amount of salt. The cone's important: Ideally, it should be printed with Lorem chipsum fake newsprint, as an act of sticking two fingers up to the elfin safe tea that banned the real thing. The great thing about eating chips out of a cone is that all the crunchy bits settle to the bottom where they may be enjoyed last.
I eschew vinegar as it tends to make my tongue swell up, and I'm a closet southerner so - while I accept that it's delicious - I'm naturally wary of that radioactive green stuff that goes by the name of 'curry sauce'.