Yes that is common, I think its better that way so you don't have tabs to add, (Which make for more troublesome connections.)
I have seen chassis with solder tabs that are part of the chassis that are punched out with one side still part of the chassis as a grounding point. Anything held down with screws as far as tabs, connector strips, and connectors are asking for trouble from becoming loose and not making a good electrical connection as intended.
_________________
I'm a Science Thinker, Radio Tinkerer, and all around good guy. Just ask Me!