small note, the registration seashells were only for those who weren't around when welcome bells were a thing
old users (such as myself) only got the second year anniversary seashells, because the welcome bells system took the place of the registration seashells
(if anyone's wondering, yes, they removed the welcome bells system and replaced it with the seashells one due to abuse by other members. by extension, it's also why the seashells shop is just user add-ons stuffs. so people can't abuse it by just buying and selling off collectibles from it or such)
On the topic of seashells, I actually do hope they find some other way for us to earn seashells, considering it's only used nowadays for add-ons. Additionally, I'm really confused... I only have 5 seashells LOL. I wasn't eligible for the first batch of seashells since I'm an old member so I only received 10 seashells total, and I have no idea what I spent 5 seashells on. There isn't anything sold in the shop right now that costs 5 seashells LMAO. I am assuming it's probably a mailbox add-on, but I don't recall if they ever sold the mailbox add-on for seashells (and if so, do I get a refund because the mailbox isn't limited messages anymore? heh)