Another reason is that anything on the bottom of the cage is a breeding ground for crickets. I even had crickets go into the bottom of my plants (the drainage holes) and lay eggs. I then had all these little things running all over the place. It wasn't nice. I had to remove all my plants, take them outside, remove the dirt, clean it all up - again - clean out the cage by removing the floor, clean off the counter the cage was on with some bleach water, etc, etc,; well, you get the drift. I put the plants back in and packed the drainage saucers with paper towels, but about 6 months later it happened again. This is with all the rest of the cage just having a layer of p. towels to absorb spraying water. Now, all my cages have plastic plants. Sorry all you real plant lovers. I just can't deal with the bugs from the plants. Florida has too many plant loving bugs. I don't keep any plants in my house.
I used to have them all over in Colorado. The winter was good for killing off bugs, but not here.