Has anyone yet to get the Fun Size Chortles Candy Bar Candy-Coated Sugar BBs, Candy-Coated Chocolate BBs or Box of Raisins? If so how many pets did that user have?
I got the candy bar from 20+ pets
I give out the Candy-Coated Sugar BBs. I got them as a fifth ToT prize.

I've only gotten the Candy-Coated Sugar BBs out of those, and I believe it came from a user who has ten pets.
As for the other items, I've not gotten a single one, which is a bit frustrating considering how actively I've been TOTing. But, I guess that's what preserves their value, so I can't complain. Some items have to be harder to get than others--that's what makes it fun in the end.
In most cases I'd agree with you. But with the Morostide goodies, I'd always assumed they were supposed to be like cheap candies and trinket-y things, and therefore they should all be free/cheap and easily obtainable for everyone. No worries about rarity or resale value or whatever, just enjoy the free stuff. But hey, if I'm wrong, won't be the first time.
Anyway, I wish you luck finding the things you want. Also, to answer OP's question, I've seen the Box of Raisins twice now, but didn't note where I saw them. I'll try to remember to check if I ever see one again.
Some ToT items are definitely rarer than others. is harder to get than for example.

Don't get me wrong, I don't love that I haven't gotten some items at all, but I think that the staff is just trying to do something different this year, and I'm trying to see a bright side to it, heh. I guess a challenge keeps me trying and trying, instead of just shrugging after I've gotten everything in a matter of a few days.
And good luck to you as well in getting everything that you want!
Oh, I'm pretty sure that's what they're trying to do. And good on you for looking on the bright side! I'm just saying, I'd like it if all the Morostide items were easy to come by, because it's a holiday.
Well, to be more specific, the Trick-or-Treat items - since there's so many different ones and they usually come out in waves. The Patch items though, it totally makes sense to have some of those items be more rare than others.