From a Halachic section of a weekly flyer. I don't remember which one; I don't believe it's around anymore.
Free offers and Cancellation Periods
Q:
A company offers free iPods to individuals who get five people to subscribe to one of the offers of their advertisers. One of the offers is a magazine subscription which offers a thirty-day cancellation period. Question: Is a person permitted to sign up for these offers with the express intent to cancel before the thirty-day period, but still enable his friend to receive the free iPod for his soliciting efforts?
Rav Dovid Feinstein's Response:
Such a question must be addressed to someone very familiar with business tactics. In many instances, companies ar e willing to offer rewards in order to solicit customers even if they have the option to cancel. Quite often, it is worth it for them, since many people forget to cancel and end up paying. Others, although originally sure that they won't like it, reconsider and do end up liking it. There are a number of variables, but an honest assessment must be made.
