Reasoning behind built in songs made by the android device manufacturer I noticed my Huawei device comes with a built in song called "Dream It Possible".

Quick search revealed the song was made by the company itself. Didn't  look into it, but pretty sure other companies did and do the same.

What is the reasoning behind this? The song isn't an advertisement to the company. What benefit does it give them?
"Dream It Possible" is the official Huawei Consumer Brand Song. 

Therefore it can be considered as Huawei advertisement even if the song itself is not directly related to Huawei.