A composer who has much experience in the films industry and none in the games industry insists that i license the current game I'm developing.
Trying to get back to the original question.
I believe what you meant to ask is "the composer wants me to license the music he writes for the game."
When you hire a composer, there are 2 possibilities:
1) you pay him/her, and then you own the music s/he writes for you
2) you pay him/her, but he continues to own the music s/he writes for you, but they give you permission to use the music in your game
#1 is called "Work for Hire." (you own the music)
#2 is called "licensing the music." (you are given permission to use the music)
Obviously it costs more for #1 than #2, because you get more (the ownership of the music)
In small indy games that don't pay a lot, licensing is not uncommon. And in small films it is very common.
So my thought is that what the composer is asking for is not unusual, but you should understand exactly what it is you are getting for paying him/her.