CrownByStars Regardless of its reputation or how many people use it, Instant Gaming is not an official seller of EA products. The link EA_Barry posted confirms it. That means that EA won't support purchases made through that site or others like it, and it also means that these sellers can't actually guarantee that their products are legitimate. After all, if the codes aren't coming directly from EA, they could have been obtained fraudulently, even if IG itself didn't commit the fraud.
This is also a longstanding issue with Sims 3—codes were stolen or fraudulently obtained in the first place, and they pass through several hands before getting to the player, who has no idea about the source. EA flags such codes and blocks their content, sometimes even after the codes have been registered, thereby revoking access. It's less of a problem now than in the past but does still happen. So this is less about "scare tactics" than saying these purchases are a risk, and if they don't work out, you're on your own.
I can't say I've never seen this happen with codes from authorized vendors, but most of those who come back confirm that they were in the wrong EA account, or else their codes came from very old discs, where it's possible the EA App doesn't know how to handle the data. New purchases that don't work are pretty much always from third-party key sellers.
Having said that, most players in this thread have said their content shows up eventually.