Pretty sure the movie's advertising budget would have contributed towards the cost of the cars since they got a pretty big chunk of a show watched by millions dedicated to a film I'd have no intention of going to see.
Episode 1 of this new series was really good, but the over-scripted, not-funny-the-first-hundred-times "accidents" they cause are completely played out. I miss when Top Gear was more about impressive cinematography and high production values, with a bit of comedy and some banter thrown in for the studio bits. The slow-mo 575 vs Vanquish S comes to mind - brilliant cars, good review, lots of sliding around, Steve Coogan for an extra bit of a laugh etc, etc and the 330D they ran at the 24-hour race was brilliant too - again funny, well shot, not just slap-stick and stupid.
Conversely, the electric car they made (I think they called it Geoff) was a complete waste of time and not funny/entertaining at all, and now when they say "How hard can it be?" what I hear is "How obnoxious can we get away with being and how much time can we kill between the proper supercar segments?".
