SpeedFreak said:Risers offer a more customisable riding position, hence the "fad"

a temporary fashion, notion, manner of conduct, etc., esp. one followed enthusiastically by a group.
A riser bar offers the same riding position as a flat bar with stem of greater angle. The only difference being weight as you correctly mentioned, and looks!
Why don't we all just get along and bring back the pro-flex stem:

