Sneaky algorithm

Yeah they could do that, but you still have to consider that the algorithm would then run for every player, not just you. Considering all of the HQ complaining going on now, imagine how bad it would be when people want something that isn't as highly weighted for them as it is for others. All of a sudden, that resource has become even MORE scarce for them than it was before.

Then you need to consider the processing impact.  It may seem simple on its face, but once you have a weighted list, you don't just say "go" and magically get a result.  You'll need to decide how to handle it.  Of course, I don't know how they've designed HQ. It could be that when you put something up for sale, a sale request is sent to the server, given an id and maintained in a pool (a huge hash? idk) until someone clicks on HQ, at which point the server sends back an id reference to 24 semi-random sales.  That may be over-simplifying it. But the overhead to filter those items for every single HQ click would be significant.  Rather than just (for example) grabbing 24 hash keys, you need to get the "type" of every item in the pool, determine the needed percentages based on weights so you don't just always get 24 of your highest weighted item, and then actively seek out that many of each type of item. If the only way to get to a sale is by hash key, this becomes an extremely expensive series of operations.  And it would have to be executed on every single HQ click!  A database would have more overhead, but would allow filtering on type.  You'd still probably need to do multiple queries to ensure a properly weighted result. (apologies to the EA devs for what is probably a gross over-simplification for something that certainly required a lot of effort to implement)

At any rate, for the market to be fair everyone needs a fair shot at the same items. In that sense, it's more like a real market. First come first serve. How badly you WANT the item is not a factor if someone else gets there first. 🙂