I also don't think it's a slight. Also, I want to add that for some people (like me!) having 50 cookies in the house is just an invitation to overeat so I always try to get them out of my house as quickly as possible. It's not a reflection on the giver, but an indication of my lack of self-control.
Another good point I hadn't thought of! I'm glad I started this thread.
I think I made a wide variety of cookies, again, assuming people are like me. I have many allergies, so there are some things I automatically can't eat. And then there are other things I really prefer (chocolate) versus things I don't like much (plain sugar cookies) and so I think that getting one type of thing only, in a small amount, is limiting for the recipient. If I am the recipient. I was thinking of my eating habits, and only mine.
The idea of giving a variety of cookies is kind and thoughtful, but I think if you're going to give so many cookies, then you need to assume that many people will consider them something to be shared. First, because of the many reasons posters here have given for why they share holiday treats, but also because of the sheer number of sweets the recipients may otherwise have.
I have a couple of types of Christmas cookie that I make every year. They are my favorites and a Christmas tradition for me, so although I may or may not make other types of cookie as well, I
always make those two. In addition, we always have my mom's fruitcake as well, so that's another dessert. If I received 50 cookies from someone, I would appreciate it, but no matter how wonderful and delicious those cookies were, they could not replace the sentimental value of our core traditional Christmas cookies and fruitcake. So, I would have 50 cookies, plus my two batches and the fruitcake. If one or more other people decided to give me cookies...well, the number of cookies would keep skyrocketing, at a time of year when most people are already eating lots of delicious but fattening food.
If knowing your cookies will be shared instead of consumed just by the family bothers you, for whatever reasons, then I'd suggest cutting back to much smaller numbers of cookies. I think 50 is just too many to expect that they won't be shared. Also, like others have said, sharing cookies with party guests isn't a rejection, and it's not really even giving them away. It's inviting people the host cares about to come enjoy their bounty of sweet treats
with them. And it's a way for them to enjoy and use the lovely gift you gave from without overdosing on sugar or regretting that they've ruined their diet.