This is actually an ingenious way to use this tool, to be honest. It may seem pointless to do but if you are looking for more space in your freezer to store ice, this could be a solution. Yet, just because it could be a solution does not mean that it is probably the best solution. It may also take up too much room in your freezer to warrant it being in there in the first place.
As for if they could be used in this manner, they certainly could but they were more designed to be a vessel to refill glasses and such. Much like with the last question, there are superior products out there if you are looking to store ice in your freezer.