I am really not sure what you mean. As far as I know, they simply print the PDF page. If you are talking about printing to PDF, they have to have Acrobat, not Reader.
The "Print as image" or print as picture is a sticky setting for a printer. If you will once check this option ON, it will remain ON for that printer till the time un-check it.
Is the option not behaving as the above mentioned expected behavior?