I think the immediate reaction from people invested into Bitcoin would be negative, when they hear that some new Alt coin or "Blockchain" based technology was launched. You immediately think that money will flow away from Bitcoin to these Alt coins and Bitcoin will lose investors.
Could a new coin attract new investors to the whole Crypto currency scene, that would not have invested, if it was not for this coin?
Let's say for instance "Mc Donald's" launch a new Alt coin, called "McCoin" and Billions of people starts to buy and sell these coins. What would the natural spinoff of this be? I think "increased awareness" of Crypto Currencies. A percentage of these people might start to trade other Alt coins or Bitcoin as a result of this.
Do you think this is Good or Bad for Bitcoin, when this happens?
It will create a positive effect to Bitcoin since it is the first cryptocurrency ever created and none of those altcoins would exist if Bitcoin wasn't invented in the first place. Even if there are millions of new altcoins coming in and trying to replace bitcoin or correct bitcoin's flaws, BTC will remain the king of all coins because of the mere fact that it has already proven its performance in the market and it is considered as the best store of value of all the cryptocurrencies.
There are still lots of people who have no knowledge about bitcoin, so its one way of advertising bitcoin through a new cryptocurrency or project. In every cryptocurrency that is being made, bitcoin will always be the basis of them all. Those altcoins were made out of bitcoin's flaws so with these new innovations ( new altcoins or project ) it is one way as well of getting the word out of how awesome blockchain technology is as well as bitcoin as the first application of this greatest invention.