we were taught to take three sips of water before we ate, The Father, The Son, and The Holy Ghost.
Interesting you said this, but one of the real nice families that I know. Told me something similar. They carried a water bottle and made sure to drink some water, before eating anything. It was from them that I actually learned about that, previous to that I never heard of that. I wish I would have been told, but I don't remember hearing about that. I guess I never really thought about it. I never immediately eat after mass anyways its usually like 30 minutes to an hour later, sometimes even more. So by that enough saliva has really been swallowed so that no particle is left in my mouth. This applies to all those who carry around cookies, snacks etc... I just eat real whole food, I don't put junk in my mouth anymore (not that it is sinful, but just personal preference).
I guess it also depends, is the person who is consuming the food one who received communion. Whether you receive communion or not, you should always say a Thanksgiving prayer.
I could see how an older person who needs to take medication might do such a thing without fear of scandal. The best thing to do when it comes to things of this sort, is to give them the benefit of the doubt and might be good to remind the people handing out the stuff about that.
Now of course, you said a Conciliar Church. In the first place you shouldn't be there, but if you HAPPENED to be walking around. Then noticing such a thing, could happen all the time.
For all purposes, the Novus Ordo is an Anglican type of situation. You have your High Church Anglicans, broad church, low church and it really depends who the president of the assembly is.
If he is remotely Catholic and has some Orthodoxy you would see much less of these things going on. Even more if the President, is celebrating some indult either every day, or weekly or monthly. They tend to be a little more doctrinally sound, but it really depends.
In my whole "diocese" within the Conciliar framework, more then 100+ "priest's" and out of all of those just 1 has the Catholic faith. Another one, is heading towards the right direction. That is just in my own city, but it just gives a clue as to how bad things are.