Speaking as a member of the church, I've heard the position that, when in financial difficulty, first rely on family (where applicable), then rely on what's available through the government (which includes food stamps, unemployment benefits, etc), and finally rely on the church. I wouldn't see an issue with someone receiving aid from all three sources, even at the same exact time -- if a person qualifies for food stamps, then the church can spend an equivalent amount helping someone else, and perhaps help with other bills regardless.

I think the problem is that "communism" has a ton of baggage that implies a lot of things that aren't actually part of communism. Communism is actually a stateless ideology, which is completely different from the common usage of the term in describing countries like China and the USSR.

With the law of consecration, there's a clear, but voluntary state, and the end goal isn't the dissolution of the state, but the ending of the expectation to give up your property (the law would go away, but you'd continue to give because you want to). It's not socialism because it doesn't matter who owns the means of production, it only matters that the production is given to the church to be redistributed. It isn't communism because there is a clear state, but I suppose it's close since ideally there wouldn't be any social classes or coercion.

The main similarity is the ideal of "from each according to his ability, to each according to his need", but I think there are enough differences to make it reasonable to say it's not communism, but it is a collectivist system with similar goals.

I think the key difference is the Church's system is voluntary and communism is not voluntary.

That difference means everything in the world.

State communism might not be voluntary, but there are plenty of forms of communism that are voluntary: employee owned companies and cooperatives are literally communist.

And I don't really consider it voluntary if I am to believe the consequences that they teach: the threat of being ripped from and permanently separated from your family for eternity is just as coercive of a punishment as the threat of being sent to a gulag.

Nobody I know teaches that, in that way, but that some opportunities and blessings are gained or lost based on our choices: to say otherwise would be simply deceptive. Most marriages say "until death do us part", or such, or assume it, but eternal promises do have requirements to be met. God is both merciful and just: one attribute cannot rob the other. He gives us real choices, too.

Mormons might be confused given Ezra Taft Benson's use of the church and his position as president and prophet to literally promote the John Birch Society. If there was any indication from god that communism was evil, mormons believe it would come from their prophet, and in this case it did, thousands of times over.