You bought because you wanted it.
LFS as it is now is very playable and has little bugs. Go play GTR2 and see a lot more bugs. You want collision detection? Go see how its modeled in GTR2 and have a laugh.. This is only one example, i can be all day here.. but i have my point.
I don't care if its alpha or whatever, for me it looks like a complete sim and i know it can only become better in future.
Sure i miss some new content, but don't claim devs because you paid something with no guarantee of new content.
Cya