LaTeX's standard styles use two page styles, one on normal pages and one on `opening' pages with \maketitle or \chapter etc. Unfortunately there is only easy access to changing one of these two so if you want something other than `plain' on the opening pages you must use \thispagestyle on each such page. The
fancyhdr
package does provide a more flexible interface, but if you just want an empty page style on all pages then this package will do the job.