MIT/BSD are free software though; Open Source adds licenses that allow viewing the source, but have various restrictions on redistribution. They're just not copyleft. Regarding Android, Google provides the source, and there was nothing precluding them from using something like DirectFB instead to build android on. With such a system, you'd end up with something that looks a lot like gtk/gnome, which "...is licensed using the LGPL license, so you can develop open software, free software, or even commercial non-free software using GTK" [1].
Additionally, it makes for awkward copy. Made with GNU/Linux can be mentally parsed a few different ways; it could mean they're joined, or could mean an either or. Furthermore, the FSF shows their pettiness in other ways, such as how they cram GNU/ into the names of Linux distributions that don't use it [2]. Their actions on this front just end up feeling petty and petulant.
Additionally, it makes for awkward copy. Made with GNU/Linux can be mentally parsed a few different ways; it could mean they're joined, or could mean an either or. Furthermore, the FSF shows their pettiness in other ways, such as how they cram GNU/ into the names of Linux distributions that don't use it [2]. Their actions on this front just end up feeling petty and petulant.
[1] https://developer.gnome.org/gtk-tutorial/stable/c24.html
[2] http://www.gnu.org/distros/common-distros.html