Yes, well, maybe less people bought them? It's been 6 years since the big Tamagotchi boom, and the demand for toys has changed a lot since then. Tamagotchis just aren't so popular anymore; I never see people with them, these days.
Even though they were fun 6 years ago, even I don't play with mine now. ^.^; I suspect that mine have ended up like so many others; left somewhere in a box to, well... not exactly rot, per se, but never be played. ^.^; Then, they're taken out maybe once a year when you might get the urge to play with a Tamagotchi, but usually, a few hours later, it's back in the box, left to be forgotten until the next year, when the cycle continues.