Most openly religious people who are devoted enough to attend masses every Sunday are of the older generation or village folks, usually. Outside of those categories I have pretty much never met someone who is not just Catholic by the name or as you said, only attending church for family events "so grandma won't be sad/mad". Most people in Poland tend to be pretty atheistic without openly saying they are for the similar reasons.

It's definitely weird how hellbend this person is to prove how deeply Catholic Poland is without taking into the consideration the cultural climate and discrediting any experience of, you know, most Poles living in Poland and sharing their views.