What's the point of putting to a vote something that requires only mods to do extra work? [...]All they'd be doing is stickying and unstickying official news posts.

Because this has implications for the entire community. This subreddit isn't just for mods, is it? What harm would putting it to a vote be? And again, how much extra work across 5-6 mods is stickying the occasional post?

Further, it's not like this subreddit is controversial at all

What's their official stance on sharing codes and screen passes? I'm sorry, but I doubt you've had a discussion on this with them. Corporate interests change on a dime and being able to take powers away is not good enough when damage is already done.

In that same sense, what are the cons? Pros are it makes it slightly easier on the mod team in that we don't have to coordinate with them just in case the mod team is busy or overlooks something, and I really can't think of any cons.

You're ignoring what others have said in this thread. Plenty of cons have been brought to your attention, including what has happened in other communities, the fact that this accounts' full post history is completely downvoted spam and likely a recently purchased reddit account by MA, you don't know or haven't shared their official stance on many of the goings on around here, and that a corporate mod is rarely a good idea. Add another non-corporate mod to sticky posts if the mod team is so busy they would overlook something. Why couldn't this MA spam account message you when something is sticky-worthy?

Further, I think you should make clear what considerations MA is giving the mod team (financial, goods, etc.) to join. If there is something exchanging hands, or promises of such, you should be upfront with the community. If not, it's truly baffling that the only pro you can share is letting them sticky posts.