A woman who thought she was allowed to vote (she was not, as she was a recently paroled felon) got sentenced to a five year prison sentence for it. Another woman voted illegally as a green card holder, sentenced to eight years.
So you are suggesting that the major political parties would sanction, even informally, having people go out to houses to illegally harvest ballots, or throw out ballots they don't agree with? To get one nearly worthless vote at a time, with a very possible multi-year prison sentence for each. That is utterly ridiculous.
It's not illegal in California. The major parties do send people out to harvest ballots. Nobody can tell what happens with the votes. Some people's votes are sure to be discarded. Some people hand over unfilled ballots, with or without signature.
If California allows unsigned ballots, then they have a legal problem to fix. Just because they do it wrong doesn't mean it cannot be done right.
I can't imagine many votes have been discarded, that sounds more like a conspiracy theory. It wouldn't take long to get caught, since voters can easily verify their own vote was recorded.
So you are suggesting that the major political parties would sanction, even informally, having people go out to houses to illegally harvest ballots, or throw out ballots they don't agree with? To get one nearly worthless vote at a time, with a very possible multi-year prison sentence for each. That is utterly ridiculous.