Why did Ripple do a giveaway? Was there ever a stated reason for the giveaway?

Was this in response to the ridiculous criticisms they received such as "centralization" and concentration of wealth?
The best description of XRP distribution/giveaways I've seen is on Ripple Labs XRP Distribution web page.
The whole page is worth reading, but I'll just include a few select quotes that may address the question:

Users don’t need to hold XRP if they prefer to transact in other currencies (e.g. dollar, euro, yuan, gold).

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The inventors of the Ripple protocol created 100 billion XRP at its inception, and no more can ever be created according to the protocol’s rules. The creators gifted Ripple Labs 80 billion of the 100 billion XRP in existence.

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Ripple’s method of confirmation, called consensus, doesn’t need mining; therefore, it requires comparatively negligible computing power, confirmation time adapts to network latency, and transactions are immediately irreversible once confirmed.
Because Ripple’s new architecture does not require mining, the creators of Ripple had a choice: distribute XRP exclusively via mining or diversify the distribution methods.
Distributing value is a powerful way to incentivize certain behaviors. Bitcoin’s mechanism, for example, led to an explosion of processing power devoted to bitcoin mining. Our goal in distributing XRP is to incentivize actions that build trust, utility and liquidity in the network.