So, as I only found out today, you can convert any spawner to spawn any animal as long as you have the corresponding egg to do so. This is a standard 1.8 feature.
Now this is an issue on several levels:
- I am still selling eggs in the shop. How much sense does it make to sell a horse egg for 1000 Uncs when someone buys it and then sells live horses off his lot?
- The whole value of any animal where a spawn egg exists is practically zero because of this. I am a bit disappointed on this possibility because I felt that there are already too many things that are too easy to get.
- Changing this behavior is quite tricky. Everyone who used this so far will have an advantage beyond everyone who comes afterwards.
So I basically now removed all my spawn eggs from the shop. People will have to get looking again or work together to get the animals.
If anyone has an alternative solution, please let me know.