Is it only appearance though ? When using free open-source software, the license always disclaim any warranty or liability related to the use of the software (the famous THE SOFTWARE IS PROVIDED "AS IS"... paragraph).
When buying the same software from a vendor, the contract may include not only warranty & support but also some level of liability in the event of a software/security/design flaw.
When buying the same software from a vendor, the contract may include not only warranty & support but also some level of liability in the event of a software/security/design flaw.