Bb Soprano sax reed vs Bb Clarinet reed

I tried a Bb Clarinet reed on my Bb Soprano saxophone. I did this out of curiousity and not for any particular reason. I was surprised when I found out that my clarinet reed fits on the soprano saxophone mouthpiece. Also surprising is the rich, dark sound my soprano has with the clarinet reed. I put the soprano sax reed back on just to verify. Why?

What is the difference between Bb Clarinet reeds and Bb Soprano saxophone reeds?

Is it just my particular Bb Soprano saxophone mouthpiece or do all Bb clarinet reeds fit on Bb soprano saxophone moutpieces.