any reason why?
I'm guessing there's a ridiculous plot element involved.
( Moon Girl Technologies horrendous beanbag, Wed 27 Aug 2008, 10:34, archived)

I think the forcefield windows are only alluded to in
First Contact, as an example of how vast the gulf in technology is between the 24th century and the point of first contact.
( WormuIus, Wed 27 Aug 2008, 10:36, archived)