The ethereum blockchain have opened up a lot of possibilities and this is one of them,  I have hard of forks creating tokens out of nothin and what you should used to determine the worthlessness of a coin is the value attached to it,  so if you see any coin that is worthless and delisted from exchange that coin is a good example of a token that is created without money or zero value. So it is as simple as that and if have to understand that that accepting such tokens into your wallets may end up becoming spam tokens in the long run.