Here's our experience:

2010 ... went to Paris and the French Embassy didn't ask us to submit details of flight or hotel booking.

2011 ... went to Rome and ... in total contrast ... the Italian Embassy expected us to supply BOTH.

Seems European Embassies are a law unto themselves ... ... since it is my understanding there's never been any actual legal obligation for the spouse of a British national to provide such paraphernalia in the event of married partners travelling together.