Maybe it's just me, but I give things to people because I think it will make them happy. That's my aim. Thank you notes are not necessary for me to feel appreciated. I don't stand on that kind of ceremony. When I get a gift I thank the giver in person and possibly follow up with an email or phone call. Or not. It doesn't seem to matter to the people I know and love.
I give boxes of homemade Christmas cookies to many friends during the holidays and mail at least another 20 boxes across the US. Some people thank me in person, others call, some FB message me, some email, some make no reply whatsoever. I always double check tracking to make sure they arrived and leave it alone after that. Sure enough, within a month or so of the holidays - whenever it is that we next get in touch - I hear how much they enjoyed the cookies. Of course, that was my intent in the first place so it's all good.
Life is short. If when I'm gone, some recipients will reflect happily on their Christmas cookies, well that's all the thanks I will ever need.