WHY DO WE UPGRADE OUR SUSPENSION

So do I! Because I know EXACTLY how much the stock suspension is capable of, so when I spend a lot or a customer does, I make sure they get as much for their money as possible.
I've found some cars where you could get more camber than some others.

I would venture to guess mopar guys don't need a rear bar. Its very common to have high ride height and/or springs in the rear that are too high rate. The best thing to do is test. If you are lucky enough to be able to drive in a large circle with increasing speed, you will find which end lets go first
My 71 340 came with the factory front and rear bars still on it when I bought it in late 86 and with good bushings etc. It was a bit loose but I like them that way. A car that pushes pisses me off lol. My 92 318 reg cab short box Dakota had lots of push in it but a good stab on the loud pedal usually induced way more tail happiness than anyone would care to have. Funny how the same size Dakota with a V6 handles so much better with less weight on the nose....especially with 255-65-15 GY Eagles on 8" wheels. Front bar only.