If past is prelude, then the volcanic eruption in Iceland whose plume of ash has grounded almost 300 flights across Europe may not only affect air travel in the coming days, it may also have a lingering impact on Europe’s weather. Experts are looking back to the aftereffects of a previous eruption–when the Laki volcano in Southern Iceland exploded more than 200 years ago. That explosion had catastrophic consequences for weather, agriculture and transport across the northern hemisphere – and helped trigger the French revolution .The sun was covered for eight months at that time.
Crops need seasons and farmers in Europe may have an impact this time if there is further fallout.

People returning to UK will likely have commitments perhaps work or family responsibilies and several days in any airport will be trying to say the least.Oil workers offshore are affected here.
Hotels will be costly and what has been said is that "This is an act of God" so no insurance will be paid out.