Speaking for myself only, and note my name - when I get free coins on poloniex (via giveaway, trivia contest, etc), I sell them immediately if they have any aggregate value above, say, .005 BTC. The exception would be if I had overwhelming evidence that the coin was rising in value.
That does not contradict my point at all.
I hold a few currencies, let's say USD, EUR, silver, gold, BTC and XMR. If anyone gave me a freebie in any of these, I would keep it and not search to convert it until in the next rebalancing.
If the freebie was in any of the other currencies, I would seek to convert it to some of the ones mentioned, to ease accounting.
Even if it was in the list, if it was large in sum, I would have to do the rebalancing sooner, converting some of it to the other currencies.
If it is very large, even if it was BTC, I would sell a part of it to keep a balance in my currency/metal/RE/project portfolio.
So the point remains. What coins you regard fit for investing, is a different set than what you might receive as freebies (even if counting botnet gains as "freebies" is disingenious, since mining a coin with your stolen resource is a clear business decision, it is just not an investment decision).
I have received genuine freebies such as 35,000 XRP last year, and the day I received it, I sold them for BTC.
To make giving freebies a good way to increase the popularity of a coin, you have to make a very good scheme, and nobody has succeeded so far. I am trying with personal circular donations here. That the giveaway is happening only via trusted personal relations instead of an open application, is a step in an uncharted territory, after all the charted territory has been proven to not work
