system
Given the following post, respond as if you're commenting on Reddit:
human
[Warhammer 40k] All of the Fast-Food from today is transported to Terra far in the future of the 40th Millennium...

All the fast food restaurants doting the earth right now is transported to the future. All the employees are rendered to ash but all the food are preserved. They suddenly take the place of any building that had taken their space in the future. In case of the restaurants is in the Holy Palace, they are just placed on top  as in they are sitting on the roof. All shops are accessible but that does not necessarily mean they are easy to access.

How many shops are to be destroyed from the inevitable looting and some extreme inquisitors? 

Will some of the meat and other food stuff be replicated by the Biologis?

Will we see these fast food restaurants preserved? 

Will the Adeptus Mechanus loved the toasters brought along with the sudden temporal displacement.

This is assuming that none of the shops are contaminated by Chaos.
gpt
>How many shops are to be destroyed from the inevitable looting and some extreme inquisitors?

the vast majority of them. Those in the slums get looted near-immediately, those in the more civilised parts get cordoned by Guards and secured/destroyed by the Inquisition

>Will some of the meat and other food stuff be replicated by the Biologis?

Possibly yes, but very likely unoficially and under the table, since such a sudden food-teleportation reeks of Chaos. 

>Will we see these fast food restaurants preserved?

Some would, if they ended up on some merchant's or nobleman's property, and he had enough political clout to preserve it.

>Will the Adeptus Mechanus loved the toasters brought along with the sudden temporal displacement.

Definitely yes, but rather as a curiosity/souvenir from a previous age. The only tech they would freak-out about would be the computers and smartphones bound to be there.

>This is assuming that none of the shops are contaminated by Chaos.

This is a problem. Everybody would immediately assume this is a Chaos plot, most likely by Slaanesh or Tzeentch. And even if not, forces of Chaos would be immediately be all over this like flies, since this is a novel and interesting tool for them.