I can't comment on the size (so LW is growing?), but I have a tingling memory that long time ago (several years back) people did post LW quotes. Since LW doesn't exist that long I suppose it was the case in its inception. I can't say for sure, but actually Eugine's post seems to suggest that as well; otherwise it wouldn't have been "creeping into". Either way, should be easy to check. I do, too, think it is worthwhile to put LW quotes. I remember (I do!) reading those and being led to read the original articles whence they came.