The food truck special items are not populating? Are we not able to get them if we got them in 2017?

You can only collect the secret food truck items once. So if you got them in a previous year, you cannot get them again.

They don't reset, which is a shame because I've gotten different pets since then and while I only got 2 of the secret items before, one of them (the cheese one) is over 500k and I'd rather not have to spend that much on it, I wish they would reset them between when they bring them back again.

Yeah, I wish they would reset as it's been years