More Choice In Making Purchases
The company would probably make more money from purchases if it gave its customers the freedom to better customize them. Many times I would have been happy to simply make the purchase if the deal had been for the rubies the deal said it was the equivalent value of, but I didn't because I didn't want or need a lot of the stuff arbitrarily thrown into the deal. So a simple option selector to get one or the other ( the package deal or just the rubies it's equivalent to ) in the deal would increase the chances of a sale.
If someone wants to get really creative and not just offer rubies, have a menu of all the available sale items that customers can select à la carte from. Giving customers choices always improves the chances of sales, and it's easy to do. Preventing customers from spending their money the way they want just frustrates them, ticks them off, and that makes the likelihood of sales less, and reduces the desire to play the game at all. I simply don't shop where I can't spend my money the way I want to.