We have 3 cats, well, 1 kitten and 2 adult cats. I swear they are constantly hungry or looking for food. They are fed twice daily, once in the morning and again in the evening. They have high quality kitten/cat biscuits with premium tinned food, fairly decent sized meals, but they still seem to scavange where they can. They carry on at every meal time like they haven't been fed for days, constantly trying to eat from their bowls while I am still serving their food, and when it isn't meal time, they are scavanging for scraps or trying to eat from my plate, and I mean every single meal, as soon as I sit down to eat, the cats are right by my side eyeing off my food. They are wormed, so I don't think that is the problem.
Anyway, is this normal cat behaviour? I have no idea as we have never owned cats before, these cats are my sisters, but as she is often out, I am pretty much the one feeding them.