examples/embedding_in_* don't always use font specified in matplotlibrc

I'm using 0.86.2 (Debian 0.86.2-3). With the following line in

    font.sans-serif : Courier 10 Pitch, Bitstream Vera Sans, Lucida Grande, Verdana, Geneva, Lucida, Bitstream Vera Sans, Arial, Helvetica, sans-serif

when I run
    python embedding_in_wx.py
    python embedding_in_wx2.py
    python embedding_in_wx3.py
    python embedding_in_gtk.py

I see the Courier font used. But when I run

    python embedding_in_gtk3.py
    python embedding_in_qt.py
    python embedding_in_tk.py
    python embedding_in_tk2.py
    python embedding_in_wx4.py

I see the Lucida Grande font used. Any ideas?

Thank you,
Glen Mabey