A well-designed event allows people to participate without attending (by collecting their opinions beforehand, by phoning them during)
A poorly-designed event* allows people to attend without participating (by creating sage-on-the-stage models, of the Great Speaker and rows upon rows of acolytes, or forcing people into the role of ego-fodder.)
Which do you, dear organiser, want?
Do you want zombified potential-participants (ooh, look at the bums on seats), or do you hope to create the conditions for the flowering of energised sorts who give a damn, and respect for those who aren’t necessarily in the room?
* Of course, “well” and “poorly” depends on your goals. If you WANT everyone to pay attention to you, to listen to YOU and take their orders and ideas from YOU, then… you are at heart an authoritarian, whether “left” or “right.” If you want people to connect, to learn from each other, to teach each other, to identify the gaps in their knowledge, the missed opportunities and mis-steps in their past actions, then sage-on-stage, the default setting, is clearly totally inadequate. But is easy and no-one blames you when you do it… So it continues (for these and other reasons.)