I've listened to this several times now, and I can't hear he sings anything other than "like cheaper fuel" - and I've always thought he sang nothing else. Other people have confirmed what I hear. An Iranian oil strike in late 1978 lead to the early 1979 oil crisis where fuel prices rose considerably - it could be that was on Cliff's mind when he recorded this at the time. Being British, he would pronounce perfume as 'PER-fume', so it would be hard to sing it differently. Anyway, the young using up their freedom like cheap fuel sounds so plaintive and so very much better. (He mouths like 'cheap per-fume' in the video, but this was recorded after the fact). Of course I also much prefer my lyric "Carrie had a date with the wrong kind of fate - It's plain to see" - this complements the dark tone of the song much better as well.