I think 11-20 are all spawned ones and 30-40 are baddie ones and the rest are all dig/bush/grass. (Came up with this theory with NCJ).
Found 18 in front of Master Li's.
Edit: Didn't see Santa's post.
Honestly your theory makes complete sense. I'm just worried that they may have thrown a curve-ball when making this and that (for a random example, 33) might not actually be from baddies... and they're trying to trick us!
But we'll have to wait and see. I'll keep hunting!
I have this weird problem where I can't hold my eggs up when I equip them.
Same. Quite a few other people have noticed this as well. And to be on topic, I think there is some randomness to eggs, as I found as low as #2 and as high #46 from just digging.