Its not about licensing its about fair use of space taking in consideration with power and frequency. I mean I could come along and use a 12.5W burner transmitter and then nobody would be able to talk except me. This is kinda the same as what you do when you use your 4-5W transmitters in an area of spectrum designed for 0.5W.Not being facetious but is a licence for those similar to a dog licence nowdays considering the circumstances of our limited usage?
You may also feel its over regulation or needless licensing, but I know the other side of a deregulated, no license "free for all" (such as the TV spectrum in Milian) and trust me, you don't want that.