Noun: panic buying
This colloquialism is used to refer descriptively to the act of panic buying and hoarding large amounts of consumer goods: like a hamster storing as much food as possible in their cheeks to get them through a longer period of time, just in case. The DWDS recommends this article!
As a verb, to hoard things is hamstern.
Die Geschäfte haben in letzter Zeit eine Welle von Hamsterkäufen erlebt. = Shops have been experiencing a wave of panic buying recently.
A hamster in a shopping basket. Photo: pixel2013 via Pixabay