I've told this true story before:
I was in either Kansas City, MO, or Omaha, NB, for a big gathering of radical peace activists. (I've been to such gatherings in both places. I forget which one this incident happened in.) A small group of us, maybe 8 or 9, were together and one of them, a man dressed in ordinary clothing (no clerical collar or robe) put a kind of cloth thing over his shoulders and began saying Mass. (I recognized it because the Bach B Minor Mass is one of my favorite pieces of music.) I figured he was spoofing it, which seemed like a wonderful thing to me, so I went along with it. He broke a chunk off a piece of bread, ate the chunk, and passed the rest around, and each person broke off a piece and ate it, except for one guy who broke off a piece of bread but held on to it. Then he passed around a cup with wine in it for everyone to take a drink from. The guy who had not eaten his piece of bread now dipped it in the wine and then ate it.
When it was all over with I thought it was all a great joke.
The next day I learned that the man who had conducted this Mass was actually a real Catholic priest, and it was a real Mass, and I had actually taken Communion. I was surprised because everybody there knew I was an atheist, but it turns out that this particular priest disagrees with the Church on the matter of who should be allowed to take Communion. He believes that everyone should be allowed to take Communion.
So there are different ways of offering Communion within the church. They have changed with time, and are different in some places, and apparently the priest has some discretion.