If you are operating a small radio station today it is unlikely that you can afford to hire a full time staff just to play CD's and read the weather. While some stations get by on volunteer labor most will find that they need to automate at least part of their broadcast day.
Many stations use a computer to automate.
Some of my smaller clients who do not have that kind of money have come up with some rather ingenious solutions. Typically, they involve the use of multiple CD players set on random, or programmed in some way. Station ID's are inserted using a tape machine triggered by a timer or a computer. Such a system suffers from several faults. First of all, you have little control over the music.