Absolutely not. Cryptocurrencies can allow you to not only securely make payments, but also use sidechains, execute smart contracts, fund ICOs, verify authenticity, track provenance, co-opt computational resources… the list goes on. The technology is still very new and development interest is growing at an accelerating pace. New, worthwhile utilities for cryptocurrencies will continue to be dreamed up. These are still very early days in a very young space. Just like the most valuable applications of the internet took decades to be realised, so too will the most valuable applications of this technology take many years to mature.
Cryptocurrencies are a new kind of economy deserving of a whole new kind of study: cryptoeconomics. Economies usually grow organically with their structure guided by the behaviour of their population. By comparison, many of the economic features of a cryptocurrency have to be determined from the ground up. The utility of a coin is one of the key considerations in designing the economy of a cryptocurrency as it is the key driving factor behind the value of the coin.