Coal Tits storing food

Just wondering if anyone else has seen this occurence?

2 Coal Tits have been visiting our 3 seed feeders every day over the past 2 weeks, nothing unusual there.  The strange thing is that we have noticed that most of the time they don't actually eat the seed there and then, but take the seed and appear to be 'hiding/storing' it in crevices of walls and trees and even in the soil under plants in the border!  I'm presuming that they are trying to store food for when the weather turns, even though I keep the feeders constantly filled (not that they would know that though!), but did not know that they did it, nor know how they will remember where they have hidden the seed.