Why don't Laravel packages contain composer.lock?

Question

Composer

For example
https://github.com/LaravelCollective/html
https://github.com/barryvdh/laravel-debugbar

Why is the lock file not added to the repository?

Answer 1

Because they are packages (3rd party reusable solution) and not final code.
The composer.json is here to describe the dependencies and requirements of the package itself.