Is there any way round this?
You can find excellent information here: http://www.concrete5.org/documentation/how-tos/designers/making-a-t...
You could go the other way around though, having view.php without sidebar and create a Sidebar Page Type for the other pages.
The only way I can think of doing it is to duplicate my theme folder and effectively have 2 view.php files and change the site theme path links to
$v->setThemeByPath('/page_not_found', "theme1"); (view.php with sidebar)
$v->setThemeByPath('/members', "theme2"); (view.php with no sidebar)
Guess that should work!!!
Edit: Wohoo! I even found documentation on it (it wasn't only in my head obviously). Have a look here http://www.concrete5.org/documentation/developers/pages/single-page... under 'Customizing a Single Page's Appearance'.