Can you imagine a concert without them?

Yes, I could imagine one. I know they are important but as an ignorant person, I do not understand exactly what their importance amounts to.

I was told before that he's there to throw that stick at whoever goes off key or misses a note - it has to be noticeable enough tho. 

My understanding for what little it's worth is this.. Basically, look at an orchestra.. there's a huge number of people in it.

There's the violin section, the cello section, the woodwinds, the brass.. each broken down into subsections.

And they all have to play in time. Imagine trying to keep a simple beat with 70 people, and keep everybody in the same time. All just simply clapping hands.. but nevermind that.. everyone section's playing different instruments and different notes and the timing is changing a lot. Thankfully classical timing is far less tight than other types of music.

So the conductor waves at them to speed them up, slow them down, increase this emotion or that emotion, signaling them in various ways they already know well because they've rehearsed with him a number of times hopefully.

Otherwise if they all start sliding out of time it all falls to pieces. Bolero now though.. maybe Bolero you don't really need a conductor. :D

Great to have a pro around. I am just an amateur hobbyist.

What do you play Minnesota?