I've also had members forget to notify when they have received a giveaway from me. I do feel that it's polite to let someone know if you've received something for free. Also, I worry about the live plants I send out, and it's nice to know they arrived safe. I've found that if I ask a person to PM me when the package arrives in the last private message AND with a little note in the box, I normally get a "the package arrived" PM.
I do realize, that once I give something away, it's no longer mine. And the person who I give it to can do whatever they want with it. They might stomp on the box once it arrives, they might sell it, they might give it to a friend, they might love it and make it prosper and help spread it by having 100s of giveaways on this forum.
As for ungrateful people who complain about the size of a plant. I tell them that (1) the size was mentioned in the thread. (2) "Don't look a gift horse in the mouth". And (3) if they complain they won't receive anything free from me in the future. At that point, most will realize their mistake and then show their appreciation.
As for trade scams, I am very trusting but I look for a few things. I check how long the person has been on a forum. I check how many posts the person has. If they been on the forum for a shorter time than me, or if they have only a few posts, I make them send first (It's also worth checking what types of posts they make). Once their package arrives, then I'll ship out to them. After I know they are trustworthy, if we trade again, then I'll ship on the same day as they ship. (Do keep in mind, that if you are going to trade with someone else who has more post or years on you, and you haven't traded with them, you must be willing to ship first if they ask you to.)
But if something does go wrong, report it. Reports add up and can help identify a "bad egg".
What I find on many animal/plant forums, but I do not find here, is a REVIEW SECTION. I think it would do the forum a great deal of good if we had one. That way, we could report the good experiences and the bad for each member we deal with. I have a huge list of positive reviews on other forums, but on here, no one knows it. Am I safe to trade with or not? On this forum, there is no way to tell.
But yes, this is my first and only Carnivorous Plant forum that I'm a member of. I'm still having fun and I hope to continue that!