Okay, first of all, ANYONE who thought that was a Bonsly egg is one stupid sonnavabeech. As Gravy's lovely diagram shows, Pokemon eggs take similarities from the Pokemon inside and put them into patterns on the shell. To even think that the egg May got, after looking at the pictures, was anything related to Bonsly, one might as well be closing his or her eyes and guessing.
Next, color is an important factor too. That is why, IMOTBOOT (in my opinion, the best opinion out there), this leans heavily toward Eevee while also not ruling out Zigzagoon. The shade of brown on the egg has a closer to relation to an Eevee's coat than Zigzagoon. Zigzagoon would definitely use a darker brown. The zig-zag pattern HOWEVER is a little awkward and I will not rule out the possibility of a Ziggy McShiggy.
Now, if they out right said on the show that it was an Eevee egg, I don't even know why were having the conversation. But if there's still a mystery afoot, I'm going to wait to see what pops out.
EDIT: And to break the flow a bit--
Brock: LOLz look guyz a velpicks how kool
Ash: Didn't you have a Vulpix, Brock?
Brock: i dun no my mindz a littul fuzzah lol
Ash: OH WELLZ! ^_^