Display path once
From the breadcrumb view in both Nautilus (top), and Thunar (bottom) we can temporarily disable breadcrumb view by pressing Ctrl + L:
The path will aready be selected ready for copy & paste.
Disable Nautilus breadcrumbs
We can set the default behaviour for Nautilus using dconf-editor when dconf-tools are installed. Browse to org.gnome.nautilus.preferences
and tick always-use-location-entry to display the path rather than the breadcrumbs view:
Alternatively you can simply execute this command in a terminal:
gsettings set org.gnome.nautilus.preferences always-use-location-entry true
After that Nautilus will display the current location in a path view:
The file selector will then also have the additional line to add the path which also will be shown on Ctrl + L or clicking the pencil (see above):
Untick the option to switch back to breadcrumb view.
For older Ubuntu releases using gconf-editor browse to apps -> nautilus -> preferences and untick always_use_location_entry (see this question).
To my knowledge we can't change the default behaviour in Thunar.