Earlier quoted context omitted.
for (1), what you are seeing is a payment and a the "change" going back to a new address owned by the sender. This is a very common pattern of bitcoin use.
Why would there be "change" in a Bitcoin transaction? Is this: send me £10 in BTC but actually send me £15 in case the price changes and I'll send you back the difference.
Let's say you have $20 in your address, and you want to spend $10 on candy bars. A common pattern of use is to spend all $20: $10 goes to the candy bar company, and $10 goes to a new address you just created. This helps obfuscate how much money you actually have.