FFG wants everyone to buy every ship. They incentivize that (or reward it) by spreading useful upgrades across all the ships. In my opinion, the TIE Advanced "fix" was a happy bonus for getting a Raider. I never even bought a TIE Advanced before getting the Raider in fact.
I guarantee that, even as sh*tty as they used to be, way more people owned Advanceds than will ever own a Raider.
If that hypothetical case, if FFG released a "card only pack", they might be breaking their deal.
All the more reason they should let you buy individual cards online.
FFG will lose money (infrastructure that doesn't currently exist; oversight committees) and consumer faith if they ever sell individual cards. Collectors/Scalpers (~20% buyer_base) are a vital part of the business (Pareto Principle). Some of this 20% buyer_base are also gamers and the rest are just run-of-the-mill Star Wars Scalpers (i.e. wts potf2 longsaber mip). Point is... You either go back to flying for fun, or you support the Gray Market and you get that sweet Upgrade. The Gray Market definitely supports FFG. And for pete's sake, support the Commission Painters/Modders (eBay)! You can get sweet painted minis from hardworking hands anywhere in the world. And we all know the commish kids are buying a lot of models. So in supporting the commish kids, you support FFG and get bling on you ywing. hugs.
Scalpers that sell auto thrusters for $6.75 a card on eBay? No, we don't need their kind. They bring no added value to the game but instead become greedy middle men that mark up card prices. This is exactly why as an Imperial only player I have two Starvipers and one YT-2400 on my shelf.....