Why are these so expensive?

[ginnypearl]

Seriously, why are the plain colored Techo plushies so expensive? the blue one is around 320ish but these three are ridiculous! They also don't restock, were they given out as event prizes or something? The yellow one has a rarity of 103 which i've never really seen before (or if i have, i haven't noticed)
Anyone here have any insight on this? ^^;;

[hrtbrk]

They were a promotional item given out over 20 years ago. 

[Secre]

I mean that's not a bad price for an event item in honesty. Many rare non restock items are in the millions. It's cheaper because they're plain and a collectors item only.