Are those merit holders still active and regularly log in to this forum? If they are no longer active, we can understand why they didn't send their sMerit.
But for those merit holders who are still active in this forum, it is very unfortunate to know they don't care about spending their sMerit. Well, they may think they have no obligation to send their sMerit, but what's the purpose of holding it? No worth of holding sMerit, it is not BTC.   

Not sure to say we will have a merit crisis without merit sources. There are still many generous members who regularly spend their sMerit although they are not a merit source. But I can agree if merit sources have a big role to spread sMerit. Without them, sMerit can be very limited and possibly lead to a crisis if the awareness of spending merit among members be worsen.