In context......
even in context that particular understanding of that verse is not as some here would have it. St. Paul is quite clearly speaking of the Eucharist. How else would one partake of the one loaf and drink of the one cup which unites the one body of Christ?
As a Catholic, who beliefs most fervently in the presence of Christ in the Eucharist, the non Catholic and mistaken understanding of that verse, does not counter my argument.
That is manifestly evident, as first, the context is clearly about the body of Christ resisting and maintaining fellowship by avoiding idolatry and offenses to it. Thus the text you invoke is part of a teaching which censures having "fellowship with devils" by eating the sacrifices of the altar with them, as this signifies fellowship with those whom you eat with, and the object of their sacrifices.
"Neither be ye idolaters, as were some of them; as it is written, The people sat down to eat and drink, and rose up to play. " (1 Corinthians 10:7) "Wherefore, my dearly beloved, flee from idolatry." (1 Corinthians 10:14)
"But I say, that the things which the Gentiles sacrifice, they sacrifice to devils, and not to God: and I would not that ye should have fellowship with devils." (1 Corinthians 10:20)
And note here that "fellowship with devils' was not done by eating the real flesh of demons, (v. 19) but by eating things dedicated to false gods with pagans as part of a communal celebration. Likewise, feasts of the Lord in the OT worshiped God, by not by consuming His literal flesh. Nor is fellowship with the body and blood of Christ that of consuming His literal flesh, but by communally eating as part of corporate worship of Him who gave Himself for us.
And if done in a manner inconsistent with Him, and His selfish death, such as by ignoring needy brethren as if they were not part of the body of Christ, then they actually were not eating the Lord's supper. (1Cor. 11:20)
"The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ? For we being many are one bread, and one body: for we are all partakers of that one bread. " (1 Corinthians 10:16-17)
Both in paganism and the OT and the NT believers, "they which eat of the sacrifices partakers of the altar," (1Cor. 10:18) signifying fellowship by eating what is sacrificed, and thus he writes. "I would not that ye should have fellowship with devils." (v. 20)
And neither here or in the next chapter is the focus on the elements of the Lord's supper, but on what the Lord's supper signifies, and how it was being observed, in cp. 11 that being inconsistent with the Lord's death .
Moreover, entirely absent in Acts and the epistles is any explanatory teaching on the elements being changed into the literal body and blood of Christ, and the critical importance of receiving it to gain life in you, leaving RCs to read the desired substance into texts (in trying argue with evangelicals, as they do not need Scriptural proof texts for it)