The answer is no, I believe you are following up on the comments of other members and you have heard from them how merits don't decay right? I have not experienced it before and am yet to see any post or comment sighting a members merit got decayed after a long period of time for not sending it out.

On the issue of some members not sending out their merits, I don't think it's a big deal since it is their merit and they have the right to send it to whomever they find their post worthy or attractive. Personally I think merits should be the last thing to be discussed here since it's something that is freely given and freely received.