Thanks @pelvis for this info,
One thing I observe in buffets is that most times the buffet is for some class of guests while another type of food (packaged food) is served to a lower class of guest.
I'm just thinking if it's a tradition or maybe I'm thinking off-key.
It happens in few situations ,
Depending on the guest survey of the planners.
But generally giving a class to guests is not quite welcoming.
If you want to d buffet ..do it completely maybe you can reduce the number of invites..or u do a strict with-invite entrance.
Look up for my post on other service style