Maybe stop selling it so you don't have this issue with users coming to the forum complaining about losing their money (like I did) on a product that doesn't work expecting us to try before you buy rather than requiring us...
I don't know what you are trying to say with the "a product that doesn't work" line. You are making it sound as if we had a scenery that crashed your system or something like that.
O'Hare obviously WORKS, and it's coherent with the set of charts that are supplied with it, which were current when the scenery was made so, it's perfectly usable as it is, and it's surely more updated than the DEFAULT scenery from O'Hare.
There are users that might be entirely happy with an airport that is both visually better and more updated than the default one.
If you are not one of them, and you expect that every scenery you buy would be always current to the moment of purchase (which would be impossible, without start selling products as a subscription), then yes, you MUST use the Trial version, which is there for your own benefit.