The Rafflecopter page tab can be removed like any other page tab. This is a functionality of Facebook, not Rafflecopter. If you go to your Facebook Business Page, you can edit it from there.
As an Admin on your Facebook page, navigate to Settings in the top right of the page, on the white bar under the blue bar.
Click Settings and you will see two columns pop up.
In the left column, labeled General you will click on Edit Page
The Edit Page menu opens and two columns of choices come up
In the right column under Tabs then under Home, you will look for Giveaway - then move to the right side and click on Settings
- The settings box for this tab opens -
Within that gray box, look at Show Giveaway Tab and toggle the switch on the right to the off position. Toggle it by clicking on the white box next to On which is printed in blue.
If you click on the white rectangle next to that, the blue On disappears and a gray Off now shows.
Finally, be sure to click Save at the very bottom of the gray box. If you fail to click Save this will not work.
After saving, go back to the white bar under the blue bar at the top and click on Page
When your page loads, you should no longer see the Giveaway tab on the left side.