There is a way to set it, but it does not override Megaphones as far as I am aware. Don't agree, they are useful for catching gold sellers, just don't look at it.
Giving them away freely is problem, not just having them altogether. The idiots who aim to only insult and disturb others wouldn't bother/be able to afford the megaphones otherwise.Megas 'WERE' Cash shop items in the past. Don't know if they will be now, but I did play CDnF briefly and I could swear that I saw them as Cash items there.
Plus cheap DFO Gold, I have a feeling a lot of that will stop very abruptly when we become able to report players for such things. It makes no plausible sense to remove megaphones so people have to waste time logging into a forum in a browser. No sense whatsoever.