I have never been on tour but I do have high end equip. and the question I ask may not be that stupid.

Now if our amp is running through the board and we have ear monitors or floor monitors so we can hear ourselves(running through the board)Then what do we need our beautiful, great sounding, high dollar cabs for? Am I making any sense?
Thanks for any and all replies
You don't
need them, but you will most likely
want cabs for the unpredictable. I've done the extensive 15 passenger van touring thing around the country multiple times. I can count on one hand the times that the PA/engineer/venue was actually set up properly for the space provided.
Something is always awash and here's some scenarios...
Great PA, terrible Engineer
Great Engineer who constantly apologizes for the terrible PA he has to run
Big aluminum shack with pro PA, pro Engineer, and worst sound imaginable
PA isn't set up to run IEM's, a monitor dies, or the assistant engineer blows monitors as he compensates for the damage; they fall like dominos
The crowd is so close they can hear the monitors as well as they can the cabs
You land a gig with a pro stage that's super deep and you've never played with your drummer 15 feet behind you on a drum platform up to your chest.
The PA equipment isn't up to scratch, so it's constantly popping and crackling
There's other situations, but these are some of the common ones I've dealt with. There's a lot to be said for any of these situations, each one could be a separate thread pages deep. We got paid so we powered through less than ideal conditions at times.
On bigger tours after I left the band, they were able to scrap cabs all together. The guitarists ran Kempers line-out, and had their IEM's through a racked Mackie setup pre-programmed for tempos, a bass track, and any extraneous sounds they couldn't reproduce live. They brought the cabs just in case, but never pulled them out after they switched to Kempers.
I'm now starting a new band in which the drummer has possession of all of that equipment now, so it's a matter of deciding what really is the best setup for our needs. I'm leaning towards smaller combos, IEM's, and running the Mackie for tempos and set list programming.
Once you get out on the road and start loading/unloading every day you'll quickly learn whether you want to pay roadies, continue to DIY, and/or reevaluate how much gear you truly need.