Your best source of knowledge

Uhm in the US most graves are just covered with tossed gravel. We don't risk weed growing on our dead. Then again we have plenty of space.

I'm in the US... Anyway... just google US cemetery and tell me how long you have to scroll before you see a gravel cemetery not covered in grass. Lemme know when you stop scrolling.

Bless Your Heart. Welcome to Louisiana. And most of the south. We don't like weeds.
https://www.roadsideamerica.com/attract/images/la/LARAYcemetery_miers1_620x300.jpg

Wrong Way Catholic Cemetery. Yeah, look out a little further where the graves aren't so close and guess what? Grass.

I'm not going to get in an anonymous online argument with you about graves. If you and your parents want grass over their vault , Gosh Bless Ya.
Weeds creeping in and breaking down headstones. Tree roots digging in and breaking open vaults and coffins. But go ahead and grass over the graves of your forbearers. The people that gave you life. Your kids will probably mow the lawn over you as their kids play soccer one day.

Oh I agree, this is a stupid ass argument, I shall leave it alone amicably as well.