I am not so sure that gift and free are the words mean what some of you seem to think they do.
Free means at no expense, period.
A gift is no longer the givers, period.
A string of any kind makes any transaction neither free nor a gift.
Even something so well intended, in theory, a gesture as insuring that the giver has the snake returned in the event the givee can no longer keep it makes ownership of the snake by the givee impossible. If you can't do what you want with it, it's not yours, period. Wrap it up as pretty as you can, parfume it as you will, pretend it's anything you want, but if it's got any attachment, it's neither a gift nor free.
Period.
Proper terminology would no doubt save many a headache.