Answer:
Dogs can lick their feet for a number of reasons- they might be trying to remove something that is stuck in their pads, or have found something stuck on or between their pads that they like the taste of (i.e. if they've walked through spilt milk, tea, jam or similar). They also do it if their feet are sore, infected or injured, or sometimes as a 'boredom activity' if they feel confined and with nothing to do.