Discussions, post-mortems, analysis, inflated egos, and all that jazz.

I understand everything perfectly. There is no difference between users, whether they buy something on the site or just write messages or do nothing at all; they are all the same users.

From a legal point of view, the difference is significant: in the case of purchasing any product, including software, publishers have formal obligations to the consumer, and the consumer has many formal rights. When using a free product, publishers have no formal obligations to the user; the user has the right to use the product fully and completely on the terms set by the publishers or not to use it at all.
The standard form "Please, sign me up..." in a literary translation will be exactly "I ask you to register me..." (and not "please register me..." - this is not how people speak or write). And there is nothing bad in the word "ask" itself, there is no humiliation, and moreover, this word has nothing to do with "the Soviet era"; it existed long before: "I ask you to sit down" means sit down, "I ask you to register" means register.
To claim that someone is an alcoholic and to bring "the Soviet era" into it, to accuse someone of nitpicking words (while nitpicking oneself over one single harmless word) is the height of inadequacy or the height of conscious hypocrisy.