In an Orthodox Church, there is NO mistaking Communion for anything else! It is the culmination of the entire Liturgy!!!! And if you’re not Orthodox in good standing, you do not receive it.
In both of my Orthodox parishes, we use baskets for collection. In one parish, the baskets come around just before the Lord’s Prayer, and in the other they come around after the entire Liturgy is over. There is no mistaking the collection for anything else, either.
He wasn't at an Orthodox service...
It was the 80's and I was about to leave for boot camp. My godmother asked me to go to her church once to pray with her. She considered herself quite religious and I knew it would make her happy so I agreed.
She came to pick me up at 6AM or so, I figured that was fine because we would get it out of the way early.
Turned out that that was just the church breakfast. The breakfast ended in a whole lot of "praising" and a collection.
Things seemed relatively normal when we entered the church. I knew she went to a "nondenominational" church but certainly wasn't expecting the weirdness of the Charismatic doomsday cult I was about to be exposed to.
Over the course of several hours there were electric guitars pealing and people dropping to the ground and "sizzling", a whole lot of "tongues" mumbling, the "true believers" being knocked off their feet by beams of cosmic cleansing being whipped about by their Holy man knocking "bedwetting demons" out of members of the congregation, etc. This process included 4 or 5 more collections. "I know you've already given but the Lord wants you to dig deep to see his work carried through." I saw rings and things being thrown into that last loot bag that was passed through. Toward the end the Holy man cast a protection spell "prayed" for me, I think that cost her extra.
Finally, well into the afternoon, the service was over. I could go home...
Nope. Now comes the pot luck supper. After great amounts of tater tot casserole was slung about there was a great deal more of unusual "praising" and of course another collection.
Oh, and by the way, there was no Communion.
The point being, that while the services I have attended and those services Ive gone to at friends churches have generally proceeded as you describe, there is no good way of knowing in advance what happens and what the proceedings are when one enters some "churches".