This is completely normal. Goldfish are known to be social, but I believe they are coming to you because they are hungry. Also goldfish are not the type of fish that is easily scared. It is common for them to get along with other fish, and live for years. Goldfish are one of the most hardy fish out there.
Goldfish are known to be hungry all the time and eat everything you put in front of them. YOu have to be careful with this factor because the goldfish can become sick and the more they eat, the more waste comes out of them causing you to change the water more frequently.
Your goldfish sound fine and happy in their environment. I would not be concerned. If they are very hyperactive, this is normal as well so don't panic.
When it comes to feeding goldfish it is important to put enough food in there for a five minute feeding.(not a pinch here or there). I know this is going to sound like a lot of food, but it is not. They will eat it all trust me. A five minute feeding consists of about a half a lid of flakes. If you fill the small fish food container(the smallest they sell) about half full of fish food, that should give you a rough estimate of a five minute feeding. That is what I do for my 3 goldfish and they eat it all and then their activity level drops a bit because they are full. That is one sign to know if you have fed them enough.
Hope this helps and congrats on your new goldfish!
Hope they live a long life for you.
personal experience and the help of some research.