Who's we?
Not the OU apparently and like they say, if you don't use the OU don't eat anything processed in the US as just about every other hechsher relies on products certified by the OU.
Then again many (most?) lubavitchers won't eat anything processed at all on Pesach.
We is what the shulchan aruch paskens. there are chumras that is stated in shulchan aruch then there are chumros that people are noheg for years but is not in the shulchan aruch.
the OU will only go according to what is a clear halacha or chumra that's in the shulchan aruch, however Rav Belsky like someone said before, said that we should go according to the chumros that people were always noheg
because the OU goes according to halacha and we trust them all year, doesnt mean people shouldnt follow the chumros from their parents/community/chassidus
yhr