What?It's telling mr crow to eat it's family instead and as the result get shunned?
or maybe it's a extreme version of "accesoryless or highly damaged accesory discrimination", extreme because of something as "small" as bird poop generating the dramatic change in how her family treats her like.
Probably it's because she stinks as fuck (yukkuri standards) now. Or damaged accessory, as JIE said. Or a combination of the above.