I'm experiencing the same problem - folder is fully accessible from outside and no htaccess. Moreover, I looked into distribution archive and there're only 2 lines concerning this in admin/class.php file:
$htaccess = @array_search(".htaccess", $files);
unset($files[$htaccess]);
So there's only a check out there, but nothing's being created on install.
Can you give us instructions on how to make uploads folder accessible only from com_quicksell component?