Radio stations don’t just play their own adds as part of the stream. Most of them are part of a radio station service like for example TuneIn. And this service also os playing adds when starting the service or changing the station. Deezer uses the service and isn’t able to influence the adds. 

Yes, as @Superschlumpf said, we can’t remove the Radios ads, because it doesn't belong to us, @Hugh.Jarse .

Take care.