Don't. Don't thank them for something that is a core gameplay feature. A core gameplay feature that's been missing for 6 years.
It's nice to have, but this is something they should've included on day one, or at least in the first year, after they brought back pools and ghosts.
Thanking them tells EA that this is okay, and that if they do it again in TS5, the community will lap it up.
Unless someone specifically says, "Thank you for waiting 6 years to give us basic NPCs, please do it again!" I'm sure we'll be good.
Edit: Also, EA isn't a monolith; not everyone who works for EA is "evil" as some would say. Maxis may be dead, but there are still people working on The Sims Franchise that still care about the game. I've met people who work in the game industry and more often than not, their good efforts never see the light of day because of things out of their control (i.e. corporate interference).