Exeter has one kitchen on the main site, which is usually in a pretty poor state (although it is getting better). It has oven, hobs, microwave - pretty much all you could want. But yes, one kitchen for the whole JCR - so not great. There is hall food three times a day in the week, and brunch and dinner at weekends.
Living out - most of us take houses so they obviously have kitchen. College accommodation in Stapledon House has kitchens too, but I'm not sure what the person to kitchen ratio is.