The Hitler thing is uncalled for.
Or even closer to people in Northern Ireland still who will choose or avoid a Catholic/Protestant-owned store because of strong Unionist/Nationalist beliefs, even when the store itself has no basis.
Or a boycott on a chain of stores in the US where the owner contributes to anti-immigration policies, even when the chain itself has taken no political stance.
These later ones fall squarely under a right of free association. The East Germany comparison does not. That's why this comparison is malarkey.
With the Red Scare (which started decades before the Cold War), the government was involved early on, and at a high level. See http://en.wikipedia.org/wiki/First_Red_Scare for some of the details of what happened in the 1920s. Senator McCarthy of course used the bully pulpit to push anti-communist policies. The House Un-American Activities Committee played a key role in starting the Hollywood blacklist.
Of course there were certainly non-government pressures as well. People were anti-bolshevik and worried that the US would be overthrown just like Russia was. Others saw anti-Communism as a way to frighten people, and use that freight as a way to gain power. But without the government we wouldn't have had laws like the Taft–Hartley Act, which for 18 years prohibited union leaders from being members of the Communist Party. The Communist Control Act of 1954 is still on the books.
With Eich there's absolutely no government involvement, and the opposition is based on the right of association. Some Mozilla employees, some volunteers, some citizens, and some organizations don't want to associate themselves with Mozilla.
With East Germany, the police wanted to be involved in the actions of dissenters, and had the power to do so. With the Red Scares, the US government also used their power to force others to not associate with Communists. But with Eich .. what power do the dissenters have other than their right of free association?
That's why these cases are very different.
Mel Gibson ruined his career with unpopular statements, Tom Cruise nearly did, and nobody started talking about the Stasi then. The Stasi comment was completely uncalled for itself, a Godwin rejoinder was begging to be made.
Eich went beyond merely having and expressing an unpopular opinion. He took action to support the effort to have his opinion forced upon others by the government. He couldn't restrain himself to respectful disagreement, and that's why he's suffering more severe consequences.
You are advocating a double standard. Why is it ok for people to support "gay rights" being forced upon others by the government, but not ok for people to support traditional marriage values being forced upon others by the government? In either case, there are people who do not want the government to force those opinions upon them. So, if the majority is going one way, you're saying the minority should do nothing other than "respectfully disagree"?
The East Germany comparison is actually quite appropriate here.