They never tried to hide this - they actually thought they were building some cute easter egg, without thinking about how people would react to a phishy-looking add-on getting installed in their browser without consent or notice.
And they still haven't said "we are sorry, this was 100% wrong. we 100% promise to never again do this"
Yeah, that was a pathetic self-justifying post. "Sorry, won't do it again." would have been better. Losing their next bonus would be better still.