We don't know the eventual destination of the green and yellow planaria-arrows, but it's unlikely they led to telephones. In fact only one of the arrows leads to the phone, even though the word spawns five. In fact the entire message of the graphic seems to lead you away from the thing it represents.

Who cares? These were the coolest parents ever and your friend was lucky! They had a phone booth in their house! And a pool room! And a TV down there too.

And when you got bored, you could play with their guns!