It is by default a Basic Requirement by Joomla 3.0 onwards to disable the
magic_quotes_gpc. Otherwise, whenever a form was posted on the server, PHP would automatically escape quotes with a preceeding slash.
Disabling magic_quotes_gpc on (.htaccess)
Some hosting providers do allows you to turn this option off just by overriding the settings in the .htaccess file.
Disabling magic_quotes_gpc on (php.ini)
Some hosting providers do allows you to create a php.ini file in the document root to overrides the default php.ini settings.
If you are unsure how to do this, it's best to contact your hosting provider for clarifications.