Hello guys, I bought a trek madone and I wanted to make sure that I'm not missing anything.

I've noticed today that where my crank arm connects to the bottom bracket that there are bikes with really large spacers, some with washers... but mine looks like the crank arms slides right onto the frame... I haven't seen a lot of bikes and I've never focused on it but wanted to make sure that it's normal. The crank arm flows perfectly IMO I just wanted to make sure it's normal. Thank you.