I was listening to some stations coming in on Sporadic-E on 10m this morning, and heard S51GL answer a contact. He replied with something along the lines of: "We worked before on 20 September 2004 on 20 metres. I sent you a QSL card through the bureau three years ago. If you don't have computer logging perhaps this will jog your memory to send a card as the final courtesy of a QSO." I heard him reply to several stations in this manner, saying "I will not send a QSL for this contact as I still do not have a card for my last contact from you." I called him, and he said something similar to me, which was odd as I do not have a previous contact with S51GL in my log.
Even if I had, he probably would not have had a QSL from me as I do not reply to bureau cards. It's not a deliberate policy of mine, it's just that the chore of going through the log checking each card received from the bureau to see if it's a valid contact and I haven't sent a card already is something I can never muster the enthusiasm to get round to.
If I think a contact is worth a paper QSL I will make one out at the time. Quite often I will even send it direct, at my own expense. But I do not think it is worth QSLing every rubber stamp QSO, every exchange of PSK31 brag files, every point given out in a contest. That's just spam. Nobody needs a card from me for an award - if they do, they should say so. I think a QSL is merited only if the contact is memorable in some way, like an especially enjoyable ragchew, or someone's first-ever contact.
I do log every contact automatically with eQSL.cc, so if anyone really needs a card from me they can log on to the site and have one printed and mailed to them for a couple of dollars. It does perplex me that this hobby, which has embraced the Internet in every way when it comes to getting contacts, from DX clusters to propagation alerters and chat forums to arrange skeds, is so unwilling to use it for confirmation of those contacts. Come on guys, it's the 21st century!
It may have been worthwhile in the early days of radio when every contact was a real event, but sending a QSL to confirm every contact today is totally unnecessary and a waste of time, money and paper.