There's no way only 1% of raiders do this. That's never how stuff like this works.
Look at parsers. Maybe yeah, at first 1% start with it. But unless people really condemn it or the devs make a big stand on it, it starts to spread. I saw this with Phantasy Star Online with duping. Beyond a certain point the culture of a game changes. Usually it starts out up top, with the more casual people unaware and ignoring it, but in the worst cases it spreads down, and can reach defacto acceptance. Parsers or third party progams don't hurt as much (although you could argue parsers and fflogs culture kind of alter the game in a way that makes it a much moe adversarial thing among random players) but they are an example of the spread. If you wonder why we never got Phantasy Star Online in the west, it was because players duped and hacked so much in it (to the point of being able to delete other players characters!) that sega just stopped.
I don't think it's gotten to 100% but it sure isn't 1% reading those replies and seeing how many people in MMOs in general defend the specific practice. FFXI kind of had a firebreak preventing that mostly because the sheer time burden meant not many people did HNMS, although I think at some point even sky shells wrestled with doing it. i'll admit I use hyperbolic language, but I'm getting sick of seeing this same stuff pop up in game after game I play. Especially if the whole endgame is suppsoedly skill-based, not time based.