Agree.
Some strange things happen in meeting...often. But that is why He gave us the Holy Spirit so that we have the "inner knowing" of which spirit/Spirit it is.
Those who look at church meetings as a type of christian entertainment (which is sadly is what some of them have become) are at the greatest risk of being sucked into the wrong spirit.
We see mixture even in Job chap 1. The angels were gathered before the Lord and there in the gathering was Satan too.
It doesn't matter how good a church is, there will always be a mixture. And we always need to keep our guard up, and our inner antenna raised