That's the practical side but, more importantly, they can be worn in a wide range of colours and are pleasingly versatile: as appropriate with a soft shirt and scruffy jumper as they are with a tie and a blue blazer. As long as they are smart and tailored they are perfectly wearable in a club or at a semi-formal country house party.
Like any casual trousers they should be worn with brown shoes, and I particularly like them with my brogued boots, which gives them a suitably rugged, practical air that belies the fact that I largely wear them for Sunday brunches in Soho or casual Fridays in the office. They also go perfectly with a classic tweed jacket although avoid the temptation to ape the window displays in Jermyn street and wear cords that are the same colour as the over-check of your tweed. That's a bit too 'matchy-matchy' to be truly smart.
Both my favourite pairs of cords come from New and Lingwood, which has an enormous range of colours and a couple of different styles, including some rather nice ones with thicker, heavier wales than is usual - my yellow ones are in that style.
Warm trousers will be a joy for several months yet, and as far as I know cords are still on sale at New and Lingwood, so give them a go.