Because you can score easiler
No you can not score from a throw in.
No, you can not score on a throw in, unless a player on the opposite team has touched it prior to it going in the goal. If a player throws it and it goes into the goal without any player touching it, it's not a goal, just another throw in.
Yes, but is very very unlikely: mostly by pure luck if talking about MLS
You are not allowed to score in soccer by your fist
Hmmm that depends upon the player how exactly he throws the soccer .. in other way his aim should be perfect.. towards the net...
you really never THROW the ball in soccer...
If you do a throw in, it is because the soccer ball has gone out side of the boundary lines. When you throw the ball in it should give your team an advantage if you do get the ball from the throw in. If the other team wins the thrown you may have to fight to get the ball back what will take some time. the hole over all point is to get the ball closer to the goal you are trying to score on.
Yes. A goal keeper may score a goal directly from a throw (not a throw-in) or a punt.
a goal in soccer is to "score a goal"
Yes. A player may score directly from a kickoff, goal kick, corner kick, direct free kick, or dropped ball. A player may not score directly from an indirect free kick or throw-in.
Yes. Any player on the pitch can score in soccer including goalkeepers.