Although the contraceptive pills are designed to mimic a natural menstrual cycle with inactive sugar tablets that cause a withdrawal bleeding, but not actually a period. There is no real need to have this withdrawal bleed - it does not give you any health benefits - however it is incorporated into the packs to comfort women that their body is still working as normal, without being pregnant.
You can skip the sugar tablets both for personal or medical reasons. Some women skip them if they have a physical or mental disability that makes it difficult to use pads or tampons, others do it to avoid the PMS symptoms associated with the withdrawal bleeding. Personal reasons can include wanting to avoid bleeding for a sports event or special occasion like a honeymoon or wedding.
The only cons to delaying your period is that you can get breakthrough light spotting for a three or four days, especially during the first few months of skipping the sugar tablets, and that it may be more difficult to work out if you're pregnant. To prevent the breakthrough bleeding, make sure you don't skip a pill, take them at the same time as usual, and don't smoke.
Mayo Clinic, Birth Control, Delaying your Period (www.mayoclinic.com/health/womens-health/WO00069)