Hm, as far as I know, here in Spain there were no RGB SCART cables in stores at the time the SNES was sold (I didn't see them, but I was 13 years old and not into the RGB stuff yet). I don't know if in other european countries were sold (maybe in France).
The SCART cable that I bought for my GC (official, of course) did the fading effect when connected to my SNES, so I short-circuited the capacitors.