-When I worked inpatient, and ran around refilling omnicells, and in outpatient, where we filled 800 scripts a day, I always wore skater shoes. Not too flashy ones, they were brown DVS shoes, but they were really comfy. The only problem with skater shoes is that the heels wear out, but mine wore out after about a year, so I guess that's not too bad in the grand scheme of things.
-Insoles are ok for the first couple weeks, but then they start sucking.
-Nursing clogs are meh. They're good if you're standing all the time, bad if you're running around and getting on your tippy-toes and crazy balls-to-the-wall crap. And while we're speaking of clogs, you *could* get Crocs, but then again, you *could* get your ass laughed at/made fun of. That, and most places frown upon fluorescent colored footwear.
-In any case...you'll get used to it, and eventually standing on your feet for 8 hours aint no thing at all. When I first started, my boss yelled at me because i sat down for the first day; I could barely stand for more than a half hour. Then when I went to outpatient, I sat down a total of 4 times each day at work, once when I was working the phones, once during lunch, and twice for cigarette breaks.