We ignore clicks until we have touch data because we can't detect where the finger is and thus don't know which software button was pressed. In the clickfinger method, we should let those button events through because the chance of having two fingers on the touchpad without touch data is almost nil, but some devices like the Logitech T650 can be really easy to click without touching the surface.
http://lists.freedesktop.org/archives/wayland-devel/2015-April/021534.html
commit c14d7063b75cd68e18e3210137f2194e03b1088a Author: Peter Hutterer <peter.hutterer@who-t.net> Date: Fri Apr 24 12:25:50 2015 +1000 touchpad: allow BTN_LEFT in clickfinger mode without touches
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.