1. Whenever national political leadership makes a point of their faith—and they surely will—it will be your faith rather someone else’s on display.
2. Should your state officials decide to ignore church/state separation to promote their faith, it will be your faith rather than someone else’s being promoted.
3. If your mayor and city council decide to ignore church/state separation to promote their faith, it will be your faith rather than someone else’s being promoted.
4. If you choose to serve in the Armed Forces, you will have no problem finding a Chaplain that practices and understands your faith.
5. Whenever the federal government builds and maintains a chapel, your own religious iconography and liturgical trappings will occupy the bulk of it.
6. If you happen upon a huge monument to religion on a public thoroughfare, it will almost always be honoring your faith rather than someone else’s.
7. If you move anywhere in the South, people will ask “What church do you go to?” as a friendly way of getting to know you better. As a Christian, this sort of banter won’t prove terribly awkward and potentially career-ending.
8. If you cannot make it to a scheduled event on Sunday morning or Wednesday evening, people will generally be understanding about it. You need not explain what church services are or why they happen at those particular times.
9. During the holiday season, you will be bombarded with welcome and familiar religious iconography. Additionally, the government at every level (federal, state, municipal) will give you the day off to celebrate the birth of your savior.
10. If you are looking to get married or buried, you will have no problem finding a nice venue and an experienced officiant. When it comes to the solemnization of significant life events, secular humanists and atheists face a set of legal and logistical challenges which Christians may blissfully ignore.
No doubt there are many more unnoticed privileges enjoyed solely by members of the majority faith. Feel free to add those in the comments.