HOW TO make emails that land in Promotions go to the Primary tab in Gmail
An enterprising supermarket I go to is concerned that I may not be checking the promotional offers that they send to my Gmail account. They sent me steps on how to force Gmail to show emails they send always under the Primary category:
To disable the Tabbed Inbox feature click on the settings cog in the upper right-hand corner, go to "Configure Inbox," and uncheck everything except "Primary." This will remove the tabs and bring you back to the old, familiar, one-inboxed interface.
To see total count of unread messages (and not just the newest unread emails) click the More link in the left sidebar and you will see all your categories. The categories name will list the number of unread emails beside it.