LoTROInterface - What makes the impossible...impossible?

just like the topic states...i've noticed a lot of people don't realize that the current UI that Turbine has provided for LotRO isn't as customizable as the UI of WoW or other MMOs. I, personally, understand that we can't have our own "add-ons", so to speak, like new unit frames, all in one bags, and damage meters...but I've noticed that many aren't even aware of this.

However, I do not understand WHY we can't have all these neat features...so I'm hoping someone might be able to explain in a little more depth.

And for the rest of you searching for cool addons...sorry :( the best you'll get out of this game is skins for the current UI setup. nothing more...nothing less (yet...hopefully)