People can make up any reason they want to cut down a tree. That's not really the point. I see no problems with people cutting down trees, I see a problem with the system allowing them to clear cut a full zone a day.
You say this also wont be a "problem" once people can regrow trees. Well according to yourself, you believe they should take "awhile" Im going to assume here that means much much longer than the time it takes to cut them.
So if I were inclined I could just go cut all your trees. Now granted you could grow a few trees in your tribe area. But Im pretty sure a few trees that take "awhile" to grow will not support what you are looking to do with your woodcutting needs, and with the new decay system (great job devs), its going to require even more wood.
The problem comes with how fast these trees can be cut, and how much effort it takes to remove them vs how much effort/time it takes to get more.
Ive posted my tree opinion many times on these forums on how I believe they should change the system. I think its a good system, and Ive set to see anyone see a flaw in it.