All electrical contacts have a life. You have a limited choice anyway. You can either wear out the flash card contacts or the USB cable contacts.
I don't know what the life of the contacts are, but I'd expect it'll be in the thousands if not much more. So unless you move the card in and out many times a day, pretty much every day, then it'll last many years. I wouldn't worry about it.
_________________Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.