You would get away with it if you only wanted to carry the waders, rather than waders and boots. I have one of the older Orvis Safe Passage bags which was better designed, but even then there's a problem with the bottom part of the rod tube holders being positioned a little too high up, rather than just at the base of the bag - so you end up with rod tubes getting caught in bushes etc. more than you would do otherwise.
Being someone who does a fair amount of walking in myself, I don't like walking any distance in waders, either - but it's too much to carry both a pair of wading boots and standard walking boots. I use the korkers boots and use the rubber lug sole for walking in and then change to felt or felt studded when I get to the destination. A pair of neoprene socks pads the boots out enough to make them comfortable enough for walking and also keeps your feet dry for the trek out (i.e. after you've taken your waders off again).
Now use an Osprey Atmos 50
Atmos 50~NEW! - Osprey Packs, Inc :2012: Official Site - the side pockets are well arranged for rod tubes, the mesh gear holder/flap on the back of the pack will double as a wooden net holder and you can use the walking pole holders for a wading staff (though I just use a walking pole as a wading staff). Then add a chest pack of your choice. Even with 50 litres capacity, though, you still struggle to put a pair of boots in as well, due to the curve of the pack to keep it clear of your back/allow air circulation - but like I say, why have two pairs of boots when one will do?