I expect more if I pay more. However, how often I wear them (daily? several times a week? a few times a month?) really determines longevity. Quality can be pretty significant too. If I wear them often, as in more days than not, then I don't expect them to last much longer than a year even if they are good quality ($100 or more). However, even at the $100 price point, I think the quality varies greatly and I get better wear with some than others.
Naturalizer and Aerosoles are trashed in no time. Nine West last a little longer, but not more than a season.
I think Franco Sarto have been the best moderately priced ones for me. I have a favorite pair of Franco Sartos (pewter patent ballet flats from NAS a few years back) that are several years old and still look great. I have another favorite pair of Faconnable ones (over $200) that I wore into the ground--as in going on more than five years--and they still look good. Not great, but very good. I just bought a pair of Madewell ones that look like they'll survive a year.
Leather soles make a huge difference, but they are typically limited to more expensive shoes and you absolutely have to invest in getting a Vibram or similar sole cover put on them by a cobbler before you wear them anywhere wet. However, cheap calculated over a short life isn't nearly as cheap as expensive ones with a sole cover divided over a very long life. My Faconnable ones were the most expensive of the bunch to buy, but with a five plus year life as a favorite, the cost per wear is nothing compared to the cost per wear for my under $100 Naturalizers that were trashed in a season.
Totally with you on the sock liners (I especially love the super low cut ones they sell at Macy's). Oh, and I am seriously not joking about this, if you spray your feet with spray on deodorant, it is amazing how it helps with the stink factor. All leather construction (leather outer, leather liner and leather sole) makes a huge difference in stink too, since leather does not pick up odors the same as synthetics. If I have a pair of flats that stink and I look at them, they inevitably have a synthetic liner.