Just saying, in some countries you don't need to buy the whole packet (of pills) it's more ecological(less use of packaging, less unused stuff) and cheaper for

Just saying, in some countries you don't need to buy the whole packet (of pills) it's more ecological(less use of packaging, less unused stuff) and cheaper for the consumer...is this illegal in the US (or other countries) also what are the downsides ? (Theoretically the usage paper could be photocopied, found on the net)