If you follow the work I have been doing you will see that I have gone so far beyond 'questionable real-world advantages' and instead have identified the core of what Bitcoin is.  For starters  if you use the analogy of a company Bitcoin has a meager revenue from transaction fees and large expenses by issuing new shares to pay for security.  Thus, the company is in the red to the tune of $500M per year.   It has 2 classes of stock (voting (hashpower) and capital (coins)) and thus separates the interest of these two parties, and it is slow.

I fix these problems by actually making crypto-companies that are profitable (they produce more value than they consume) and thus can pay dividends to the shareholders.  I return power to the shareholders and the result is that the we have transactions that are as fast as Ripple, irreversibly secured by 51% shareholder vote before Bitcoin can produce 2 blocks.   You see the analogy is critical to understand the benefits.   These are tangible, real-world, advantages.   

Nothing says Bitcoin cannot upgrade to Delegated Proof of Stake (DPOS) http://bitshares.org/security/delegated-proof-of-stake.php and become profitable however.   It seems to me that this should be a higher priority than side-chains.