Yeah, it's false economy in a way.
If you park the car on a level surface and take a picture from the back of the car along the length of the side of the car so both rear wheels line up with the bottom of the picture you should be able to see if the camber is quite aggressive.
Odd shot to describe... I'll try find an example
You can actually see the rear wheel leaning in at the top, if you can see it clearly I wouldn't run overly high rear Tyre pressure as it'll just lean on the inside edge and use the first 1/4 of the tyre as it won't squash down enough to use the rest