It just doesn't make sense.
I am a very recent convert to the mooncup and all I can think is wtf was I doing with tampons all those years?
I feel almost... betrayed by the generations of women who have made the tampon the mainstream menstruation product of choice.
Ignore your prejudices because those would work either way. If you were used to using a mooncup and someone suggested carrying around a bloodsoaked wodge of cotton wool on a string in your vagina instead you would think that was gross. It's just what you're used to.
So, prejudices aside. Agreed?
Lets just look at this logically.
The mooncup produces no waste, so no flushing things you shouldn't, no filling a bin with smelly waste, no furtive smuggling of used tampons wrapped in loo roll up your sleeve when there is no bin and you don't have pockets.
It's every bit as comfy and convenient.
It's cheaper.
And it is SO COOL seeing how much blood you have lost. I'm sorry, but it is. It's much less yucky because it's not old, brown drying smelly blood. It's a fresh little pot of new, clean blood. It's just not yucky.
And this isn't a thread to critisise or judge or feel superior. I just REALLY want someone else to be converted and feel the joy too 
. I want someone else to have the scales fall from their eyes and feel as delighted as I do right now.