For some time, gnome has had really neat integration between gnome-shell and gnome-software. You can click application launcher icons. Many other distros like Fedora and Ubuntu use gnome-software as their package manager frontend. However, for Manjaro, there are many reasons not to do the same. For one, gnome-software runs as 300Mb background process, and as a package manager it simply isn't as powerful as pamac.
Now, you don't need gnome-software to get that sweet sweet integration
In gnome-control-center, applications tab lets you open apps in pamac:
You can also open apps in pamac by right clicking them in gnome-shell app drawer. And if you search for an app you don't have, pamac offers to install it for you:
Huge thanks for @guinux for making this awesome application!