What's the deal with castle tees

I always used to use white wooden tees. Now I use pink castles, although I do wish they were a different colour, as I can't see them at all.

The reason being, I used to tee the ball very high, but my coach wants me to tee it lower. The pink ones are the right height for me. If I use a wooden tee, during the round, my teeing height creeps up, until it is back where I have had it for 20 odd years, and looks right to my eye. Castles stop this.

Are wooden tees environmentally sound? Is chopping up thousands of trees to make a tee, which may only last one shot a green idea?

Castle tees are plastic, and pretty much last forever (unless your pro spends his spare time notching them with a hacksaw before sale, I'm sure ours does). However, they don't degrade when lost, but then someone else normally finds them, and they get recycled. Much like golf balls, which don't degrade either, and no one is suggesting we use wooden balls?