My attitude to "junk" and unsolicited mail

Like most folks, I receive my fair share of junk and unsolicited mail of various kinds; one good thing that has come out of the economic downturn that has affected many parts of the world since 2007/2008 is that the volume of spurious commercial junk mail has lessened considerably.

Another major category of unsolicited mail is political leaflets. For some years I have "immortalised" these in my blog, irrespective of the source, because although I have quite partisan political views, I see no reason not to acknowledge in my own fashion all such propaganda. However, my strong feeling is that I cannot imagine that anyone's voting decision has been or will ever be swayed by political leafleting. So the question is, why do political Parties utilise their funds in this way? I can only imagine they have been seduced by the peddlers of dreams, because I doubt there is much empirical evidence that this expenditure has much if any effect