I am one of those who was involved in research, well before the internet. I personally remember being asked about evaluating a "new" program, which was based in persons submitting their accumulated family files. And I was particularly enraged by a comment on the promotional material that directly stated that it was NOT NECESSARY that the material be verified. I was well aware of the long term damage of that thinking.
The concept was that genealogy was (at the time) exploding in interrest, and it was a great time where "someone" could turn that into a viable and profitable business. The expectation was that persons would LOVE to sit down at their computer and find their family online, with little or no effort.
That prediction was accurate... people now do expect to find their family tree, and have little concept of how to find that info, unless someone else has already done the research. Not to mention that by never knowing how to search real records..they don't have a clue as to why much of the online information is completely worthless.
Ancestry does offer many sources (not all of those are faulty). I think they have excellent marketing, since few new researchers realize that there are many other ways to obtain those records, that there are many records that Ancestry does NOT have. That does not translate into "research is/should be free", nor does it mean "its all public records anyway, why do I have to pay?" There are millions of legitimate businesses on the internet. That does not make them unethical. I do object to the thinking that the information is not available through other means.
I do think that people's expectations are exaggerated, if they expect that they "should" find their family on Ancestry, or any other site. They don't read the fine print.. they don't know there IS any fine print to be read. On the other hand, the membership fee, for MANY persons, is very realistic, compared to the idea that they cannot get to a library (perhaps they are disabled, have small children, so forth).
I can't agree with your statement that anyone's history has been stolen by Ancestry. The lack of records for African-Americans is a sad fact of history, but that's a whole different debate, and has nothing to do with whether or not historical records are accessible online or not.
Millions of persons trace their ancestry without using Ancestry. Others choose to utilize the services, and find it worth the fee. One is not better or worse than the other.