Suspicious advertising

You know how radio stations get singers to say stuff like "I'm [put celebrity's name here], and I love [put radio station's name here]" ? Lately I noticed something peculiar, though. (The last I heard was on Red.fm, though I'm not sure whether I also heard it on other stations) Instead of having the celebrity say the whole sentence, they have the celebrity saying everything up till the station's name, which they insert in a "special", advertisement-style voice.

Does this mean that the celebrity was actually saying something else? And they cut out the voice to insert the name of their radio station? Are they allowed to do that kind of thing??

But if that's not the case, and they actually asked those celebrities to say that...it's really dumb to insert the station's name like that. It just lacks authenticity...and you get people questioning whether you didn't steal the voice from somewhere else (like I'm doing :P ).