You can do a spray in type bedliner. Unfortunately all venues have downfalls. At some feedstores they have thinner rubnber mats and you can buy the restaurant grade mats with holes in them. Both would reduce weight a bit.
So you guys that say "no studs" don't get out and fish? I have no problem with studs. Of course I have a Al. boat with rubber covered wood decks in it. Yes the studs are tearing up the rubber, but I think thats better then calling the float short to run someone to the ER. because they slipped. I can always replace the rubber easier then a fishing partner.
Guess it would be a different story if I had a glass boat. I'd go with some vinyl flooring or something like that.
I use both studs and plain felt. I have no issues wading with either. If the bottom is so bad that using plain felts might be considered overly dangerous I suggest using a wading staff and an inflatable PFD. The no studs rule in my boat is enforced period.
I have a cataraft. I put PVC lumber across the cross bars to allow footing for all. My fore and aft casting pods have 5/8" load bearing plywood with Line-X covered decks that seals the wood for life, won't be gouged by studs and overall is just about bomb proof. Wear what you wish for your wading and floating comfort, but DON'T STEP ON THE TUBES. I wear studded rubber or studded felts in my own craft all the time. You could get some thin plywood, get it cut to fit your standing areas and get it Line-X covered. It would be lighter than those heavy rubber mats and add the barrier protection similar to the aforementioned MAGNUMS!