Most Windows installers for FOSS software make the user agree to the licence during installation: there'll be a page where the text is shown and a little tick box, you must have seen it before.
But most FOSS licences put zero restrictions on how you can use licensed software; the licences are all about redistribution. The GPL3 says:
This License explicitly affirms your unlimited permission to run the unmodified Program.
The FSF's Free Software Definition says:
The freedom to run the program as you wish, for any purpose (freedom 0).
And the OSI's Open Source Definition says:
- No Discrimination Against Fields of Endeavor
The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research.
So why do so many installers not just tell you about the licence, not just show you the licence, but require you to agree to it before proceeding? 90% of such users will never distribute the software in any form, of those who do most won't do anything other than share the installer on a USB drive. Are there reasons to make the user agree to it, other than it just being what most installers do now?