Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

[Shamelessly stolen from a source that any nerd will recognize instantly.]

The ships are only a few hundred meters across. They're traveling thousands of times faster than light in a volume of space that could be measured in cubic light-years. That's 9,460,528,400,000,000 meters to a side. Even in orbit they're dealing with a volume of space measured in thousands of kilometers.

Basically the odds of hitting a cloaked ship would be like you buying a lottery ticket for every state that runs one and winning every single one.

Why ships always face each other across hundreds of meters and are orientated the same way in the Star Trek universe is left as an exercise for the reader.