Paul Terry wrote:
However, the suspicion has always been that Union Railways want
passengers to walk past a quarter of a mile of retail outlets when
transferring between the two stations. A travelator, from which
passengers could not alight en route, would spell death to such
commercial ambitions.

This is, I'm sure, is the critical point. Union Railways is a
subsidiary company of London and Continental Railways (LCR). If you
look at the LCR Properties website below , and consider that LCR
doesn't even run the Eurostar operation but rather outsources it to
'Inter-Capital & Regional Rail', you soon get the feel for what LCR is
focused on. Which is property, and therefore retail opportunies.

http://www.lcrproperties.com/

The LCR company structure is detailed he
http://www.lcrproperties.com/html/bodies/lcr/group.html