Hm, I think he is just inspired. I noticed that by myself. When I listen to a certain kind of band, for example The Smashing Pumpkins, then I get some words and phrases from them which are afterwards to be found in my own lyrics. Even if it was not my intention to use them...
I think that ุsten is a fan of David Bowie so maybe he automaticaly uses the phrases without having any purpose to copy them
I know what you mean, but as a writer he should be conscious about these things, especially when he is a fan.
Another reason could be that English is not his native language. When you want to express a feeling or create an atmosphere with words, but you are not sure if these words work along together then you might prefer copying something that has worked before instead of coming up with something new that might sound wrong for a native speaker.