Interior doors - Snap locks & latches made of plastic!?

We have them in the house too, never before.

I only knew these things from public toilets... but I never thought anything of it. During the sampling, it was about the handles themselves (stainless steel, plastic, straight, curved...) I was very pleased that we found such an extra part, for me a new feature, in our house :) Keys get lost eventually.

after our interior doors were delivered and installed, I am quite surprised why the latch/bolt is made of plastic.

Then I am relieved :D. Our interior doors were installed on Saturday after 3 months in the house :confused:. I was also wondering why those things are made of plastic. There are worse things :)

One is simply used to pressing with full force, now 1/4 is enough. We wanted to have the [WC Riegel], but it should feel good in terms of quality (meaning smooth & sturdy) and not like in a fast food place.

One is just used to pressing with full force, now 1/4 is enough

Which alone does not mean a quality feature but merely describes your habits.

We wanted to have the WC latch, but it should feel qualitatively good (that is, heavy-running & smooth) and not like at a fast food place

Heavy-running is not quality. I think you are too much on the subject of habit. An older person, for example, would probably be more pleased about that, a child maybe too.

Have never seen anything like this made of metal in a single-family house.

Visit your grandma again, they don't have such things made of plastic there