[cynicism]There is no financial incentive for UK airport operators to invest in de-icing/snow clearing equipment. If they have passengers stuck in their shopping malls, I mean terminals, they are still making money.
Meeters and greeters are still paying for parking while waiting for delayed pax and the airport is still making money. [/cynicism]
Where I work we had 30cm of snow last Monday afternoon/evening. The airport slowed to a crawl but there was always at least one runway available. There were many diversions and cancellations but there were still about 600 movements (50% of normal January day) and yet there were complaints that we should have done better.
They were still scraping compacted snow off the taxiways yesterday after 4 days because temperatures never got above -10C and spent a lot of time around -20C (-30s with the wind chill). Because of the cold, ground crews had to go inside regularly to warm up and arrivals weren't parked for up to a couple of hours because of the extended time needed to service each flight. Inbound flow control was necessary to avoid gridlock. There were up to 30 flights on the ground waiting for gates!
Bad weather is expected here, we have the equipment for it and still it causes disruption.