Last time I had to wade and drag my yak, my rubber sandals didn't do very well. What kind of shoes do you guys wear for this?

Water shoes. Either Vibram five fingers, Fila Skelatoes, Body Gloves, Columbia, etc... I've sunk knee deep in muck with my vibrams on and they still stayed on.

I'll wear either my Astral Brewers or Columbia Drainmakers. Either are good choices, but I tend to grab the Brewers since they dry quicker than the Drainmaker.

I also wear vibrams fivefingers (my preferred choice, really) but if I know I'm going to be doing a lot of proteges I prefer one of my other shoes with a thicker sole.

I bought some mid calf length neoprene with rubber bottom wading boots. They keep the sand and debris out, keep the sun off of my ankles when in the yak and the pant legs ride up a little. I haven't seen them there in a couple years but I'm sure some where still sells them.

Cheap sneakers

Drainmakers

I wear retired Nike running shoes. Light in weight, mesh uppers, and comfy cushioning.

Fila Skelatoes, next best thing to going bare footed with the added plus of not having to be concerned about getting hooked. I also have Vibrams five fingers, but find that the skelatoes are more comfortable and considerably easier to put on.

I use these but i work for the company and get them free, and free works for me.

Tevas

I have Keen's, Timberland brand water shoes, and Vibram 5-fingers all lying around. If I know I'm going to be walking in gravelly areas, I will avoid using the Keen's, but generally I pickup whichever is hiding in plain sight when I'm ready to load up.

Although they require a little more fight to get on, the Timberland's have no "open areas" and give a nice tight seal around my ankles and are the best at keeping sand/gravel/etc out.

I like those. what brand are they?

Looks like Spenco Siesta Breathable

Personally, I would look into getting something that laces/cinches onto my foot to prevent falling off when wading/portaging.

Teva Churn

Like others have said the Columbia Drainmakers are a good shoe. I also have a pair of Sperry H2O Escapes and really like them. They are very light weight and comfy.

Definitely need to get some type of water shoe or heavy duty sandal (not flops). Even if you dont plan on having to drag your yak or portage through gravel/mud there are always hooks and pieces of trash (glass) around the docks and ramps to step on.