The only other crypto currency I can think of replacing the bitcoin is the Ethereum. Many bitcoiners are buying it.
I think so. The Ethereum trading volume is even higher than the bitcoin at the moment. So people are interested in it.
Maybe ETH is raised their moment with higher volume and passing the BTC but, if you know the ending of ETH traders is come back into bitcoin when they wanna to exchange their ETH into fiat balance.

Correct. Just trading it back and forth. Using ETH and BTC as a means of making more fiat. Small or large profit will be accepted as long there is. Seen one that does this and he always want to boast it in me.