Good points argv0.
What I thought at the first place when I posted this topic was just suggesting something that is may useful in mSL. Well, I don't really care about 'foreach' because we haven't any kind of DataType in the mSL and it's really useless, but in that way which is FroggieDaFrog just said is not that so bad to have in mSL. (However I don't care about that again, lol)
FOR loop can be useful because of some reasons:
When we writing a while/goto loop sometimes we just forget to add 'inc' or 'goto there'. (Yes, I agree with that it is our brain that makes this conflicts.) But If we could have the 'for' loop, then we writing all the things which are required (Only) for the loop in the first line and we never will forget them.
By the way, I'm agree with you again, we can do what we need by the 'while' loop and we don't REALLY need that 'for' but it could be better...

Nothing...