Value is created when two actors (people) exchange tokens (explicit things) and values (implicit things) and create an added value for both parties (e.g. satisfaction v financial return). This value can be tangible or intangible. In fact there are very few really tangible assets. Money, for example, is just a token representing values.
If, as Acland Brierty tried, you want to 'give' something (a token) away, you have to supply it with a range of values that are of interest and that are motivating to the 'purchaser' such that they can rationalise how both actors in the transaction will come out of it with the added value.
One might look at a paradigm where the vendor says that they would like to make something free (for good value reasons) and there is a way that it can be done e.g. Click on any of the Google advertisements.
Perhaps one could be less blunt about it but you get the gist. One other thing is that Google adds have very little by way of emotional 'tug' which is very important in value transactions.