Are these Addresses Invalid ones? I saw some addresses in blockchain that the format look &quot;too pretty&quot; to be valid:
- 1fuLL1xxxx1power1xxxxxxxxxxzatvCK
- 1xxxxxxxxxxxxxxxxxxxxxxxxxy1kmdGr

I assume these addresses are actually valid ones, but must never and will never get the private keys from which they are generated (i.e. No one can get the coins on these addresses). Am I right?
If I'm correct, why this guys even send (very little) coins to these &quot;invalid addresses&quot;? For Ad purpose? For fun?
You're correct, they're valid addresses, just that nobody will ever have the private key that corresponds to them.
As for why people send money to them... sometimes just for fun, and sometimes to encode data on the blockchain. This particular transaction might be a dust attack, of which the goal is to uncover which addresses are owned by the same owner, in case the owner attempts to spend the dust along with other coins in their wallet together.