Why such devotion to such a small area of the body?

Because a strong rectus abdominis (core) has a myriad of glorious benefits such as:

• Improved balance and stability
• Prevention of back problems
• Strengthened diaphragm which plays an essential role in deep breathing
• Improved digestion
• Improved heart health (excess fat around the belly is dangerous)
• Better posture (a strong core keeps your back stable which improves posture)

Weakness in the core can result in:

• Lower back pain (a whopping 1 in 4 people experience regular lower back pain).
• Over rotations in the vertebrae of the lower back (which can lead to degenerative disk disease and arthritis). 
• Digestive fires being weak (this can cause chronic exhaustion because you're not absorbing nutrients properly).

If you don't know how to get centred in your core, you can easily turn into a doormat for anyone with a strong personality. With a weak core you can become easy pickings for anyone who wants to push you off balance, whether it's a controlling family member or an advert on the TV trying to get to you buy something that harms your body. 

The good news is that every asana is potentially a core-strengthening exercise, if you engage your core (pull abs toward spine). And even more good news is that core abdominal strength improves nearly every pose, offering a sense of balance and ease.