The answer is basically the same whether one believes in the metaphysical Cath perversion or the Scriptural metaphorical understanding, which is that to take part in the Lord's supper unworthily would be to incur damnation.
But Scripturally, as seen in 1 Cor. 11:29 it was to hypocritically take part in this commemoration of the Lord's unselfish death by which He purchased the church with His own sinless shed blood, and which they believers were thus supposed to be showing.
But which they were not doing by treating others as non-members, and selfishly filling their belly, which effect was to "shame them that have not," (1 Cor. 11:21,22) and thus Paul stated, "When ye come together therefore into one place, this is not to eat the Lord's supper." (1 Corinthians 11:20)
Which means that is not coming together into one place to eat the Lord's supper if they are not doing so in order to show the Lord's death for them by charitable sharing of food and communion with Christ and others. To be impenitently walking contrary to fellowship with Christ in any way would also be to incur chastisement, or damnation as with a case as Judas. "We are thus to told let a man examine himself, and so let him eat of that bread, and drink of that cup...And if any man hunger, let him eat at home; that ye come not together unto condemnation. (1 Corinthians 11:28,34)
Likewise in the previous chapter to take part in the dedicatory feasts of pagans would be to have fellowship with demons, not because they were physically consuming the "real" flesh of demons but because of the union it symbolized.
For the Catholic the reason why a non-Catholic are not to participate is not only because they may be morally unfit, but because they do not believe in the Catholic (evidently this was originally a term for the Anglican understanding) "Real Presence," and thus as the article says, "Distributing Holy Communion to people who do not share the Catholic Faith and have not previously confessed their sins profanes the Holy Species, leads the participants to condemnation, and promotes superstition."
As if the metaphysical "real" Eucharistic body of the crucified christ under the appearance of nonexistent bread (while persons with celiac disease suffer adverse effects to the non-existent gluten) and wine (which one could get drunk on in sufficient quantity) until decay takes place (as with mold, digestion, etc.) is not superstition.
Yet, we have RCs arguing here (and on most threads where the topic of the Eucharist is brought up) that the very ACT of partaking of the Eucharist is itself salvific. Though NOWHERE in Scripture do we see that unsaved people "must" receive it in order to be saved. The purpose of the observance of the Lord's Supper is as a memorial - a reminder ever before us of the sacrifice Christ made for our sins and by whose shed blood and broken body made propitiation for all our sins. It is for those who have ALREADY received the gift of God through faith.
Not intending to offend anyone here, but it seems to me that Catholicism has too much superstition behind their adamant insistence that the bread and wine of the remembrance are literally transubstantiated into Jesus' body, blood, soul and divinity and that these elements retain their change even after the Communion service is over so that they can be placed in a monstrance for "adoration" as if Christ were truly present in his glorified state. There is outrage at the very thought that someone might have stolen the "consecrated" hosts in order to do any number of evil things to it - as if Jesus is held prisoner within the material! I just don't buy it.
What it must boil down to is that it is by FAITH that someone receives the elements of the communal observance and by doing so they are not only making a public testimony of that faith but also to be reminded of what Christ has done for us and the obligation we have to each other to remember our common bond.
Someone asked earlier if a person who is not a member of a certain church can join with the congregation in their Lord's Supper observance. I have never had a problem with doing so in churches I have visited when that happens because I DO believe in Jesus Christ. If I take my Mom to her Catholic Mass and stayed, I do not however take their communion. It is because I disavow their whole ritual of it and am not in agreement with what Catholicism says it stands for. It would be wrong of me, personally, to do that.