I'm guilty, but had a senior moment realising what I did after mailing it, but I did send a pm to let them know what I had done. I received a squishy in the mail with No info from a swap and it took me forever to find out who to thank!!! We ALL make mistakes.
I'd also like to send things in the mail without having to ask someone their addy to remain anonymous. How do I do that? I don't want to be a Secret Angel Swap pal, just someone to send things as needed to someone without having to ask them in a pm what their addy is....