“People will bring things from ace to place that are not shabbos related”
That actually has nothing to do with eruvim.
The halachah is according to Rabbi Shimon, not Rabbi Yehudah — we are lenient on mutkzeh. (That is the next to last daf in Bavli Shabbat — and one of the few examples of following Rabbi Shimon when he paskens against another Tanna.) Something does not have to be specifically Shabbos related, it just has to not fall in to a mutkzeh category, for you to be able to carry it, either in your house or in the “courtyard”. Carrying something from one end of the eruv to the other — some eruvim are many miles wide — is like carrying something across your living room.
We should obviously be careful about mitkzeh but thanks to Rabbi Shimon it is not that hard to observe. 🙂