Several times I have noticed QSO confirmation requests on QRZ for QSOs that are not in my home station log... and I religiously record all QSOs. Most of these requests are from operators in Brazil. Has anyone else run across this?
Perhaps they're "reception reports" and not QSO confirmation requests. If you didn't work the station as requested than at best treat them as simple "I heard you on this frequency at this time" type of confirmations. There are SWL folks that do collect QSL cards as proof that they did indeed hear the stations that they listen to. If you respond, it may be good to indicate the QSL is for a reception report and not a QSO. "Thanks for your reception report from my QSO with 5U4GB on 1/1/1900 @ 21:30 GMT. It's nice to know that I was making it into Palmas Brazil so well while talking to Rect in the Sylvania Islands."
Yes, I've experienced the same thing. Not just from 'DX' stations, there are plenty of them here that do the same thing. I don't log casual contacts, but do record the ones that expect a QSL. I have to think that the majority of QSLs I've gotten are legitimate, but, certainly not all of them. There can be a number of reasons for that that are as 'inocent' as can be. In general, if I didn't put it in the log then don't expect a card, sorry.
Ever gotten a QSL from -years- back, I mean a lot of years? If I can find the log and if they're in it, I'll send a card. But I don't keep logs for ever, and if it's more than just a couple of years back, sorry...