This may not be what you meant, but it seems like you're saying that if
software is not developed using an "open source" method, "open source
proponents use proprietary software".
I was not clear at all. I meant "open source proponents use the technically
better software (more features, more user-friendly, more reliable, more
secure, ... every user has her own criteria) even if it is proprietary".
Some people are most purist, and will accept a less useful computing
experience rather than make this compromise.
First of all, there are features that greatly depend on the development
method. E.g., source code auditing is essential to security. Users who want
security above all will be open source proponents and only choose open source
software that many would say is technically worse than the proprietary
equivalent. To them it is technically better because it is more secure, the
feature they value most. The sentence I clarified above therefore remains
true.
Then, there are those you call "open source purists". I really forgot about.
They are rare though. They are people who believe that the open source
software will necessarily become technically better because its development
method is better. They want to help this technically better software to
emerge (by contributing) and they do not want to spend time with proprietary
software that is doomed to be technically overtaken by open source software.
It is what they believe. Despite the reality I would say...
Anyway, the conclusion remains the same:
"open source" is about a development method that is supposed to make
technically better software; it is a technical movement.
"free software" is about users' freedoms; it is a social/ethical/political
movement.
And, of course, there are users who are partly convinced by free software
arguments, and partly convinced by open source arguments. It is not like a
user is forced to choose a camp and fight the other camp! Proprietary
software is the enemy of both "free software" and open source software"
proponents.
