While you have a point, the coins that show these kinds of pumps are only a fraction of the total marketcap.
If you only take the top 3, these already represent 80 billion of the 100 billion cap. If you then add several other big coins that actually have utility or are close to releasing that (say top 20) you end up near 90 billion cap.
Even if you discard all the "99,9%" crap, you still have between an 80-90 billion cap.
here are your top 3 (i rounded the numbers):
bitcoin:market cap: $46.5 billion
available supply: 16.3 mill coins
real availalbe supply: 16.3 mil coins. there has been no premine, no ICO for bitcoin
usage: doesn't fit in one place. it is from simple investment and store of value to being a currency to buy almost anything you can think of: from a hot dog at a food truck to a house.
You are forgetting Satoshi's stash. Can he cash out ? Or are these coins non-existing ? There are a few other big whales in bitcoin. Some have close to 1 M coins. They could cash out too, but prefer not to. That's part of the market cap.
The "merchant usage" part of bitcoin would give you a bitcoin price of the order, or less than, $100.- a coin. So the merchant usage part of bitcoin is negligible as compared to its speculative part.
ethereum:
market cap: $23.7 billion
available supply: 92.2 mill coins
real availalbe supply: less than 17 mil coins. there has been a big ICO
usage: smart contracts, and making new ICO scams.
I don't know why you say that these coins are NOT available, but the coins of all bitcoin hodlers WOULD be available. What's the difference between the ETH whales, and the bitcoin whales (including Satoshi) ? Unless the keys are really lost, or there is a lock-in mechanism that makes dumping these coins impossible, the fact that those hodling the coins don't dump, makes that they contribute to the speculative market cap.
ETH, just as well as BTC, are speculative assets of which the "real usage" has almost no influence on the market.
Note, BTW, that ETH VOLUME and BTC VOLUME are in similar ratio's as their market cap, meaning they have similar market behaviours.
If you look at total volume of BTC vs total crypto volume, you see that the BTC total volume to the crypto total volume is of similar nature as the market cap ratio's. At this moment, BTC represents a small half of all what happens in crypto. Market cap as well as volume. Consistent numbers.
And all of this is speculative. Nothing is "real economic usage value".