Do you only skate vulcs? Because these don't look any thicker or heavier than ay other cupsole, save for the super minimal ones like the Laced or Figgy.
I actually skate more cupsoles than vulc, but maybe it's not the sole. It could be the angle of the pictures or the padding, or the fact that there is not a stripe in the side of the sole that makes it look slimmer. I don't say that as a negative criticism. I'm being honest, when I looked at them (specially in the multiple shoes picture), they
looked a like they'd weight a bit more than typical shoes.
It's purely optical perception, it could be the fact that there are no logos, so my brain feels like something is wrong.
I'd probably have a different perception if there was a lakai/nike/adidas logo on it and a side stripe on the sides of the sole, or some part of the undersole that goes over the lines on the side (I don't know how to describe it accurately), like in the dunks for example
The lower blue part of the sole goes into the sides of the sole, and the red lining breaks also the perception of the sole. If it was all white, it would look bigger/heavier. It's just about perception