I imagine Contours only have problems with people adding wiring that don't know what they're doing. I assume the key fobs just expose that fact.

You can run a fused wire from the battery (or some other constant power circuit with enough overhead) to a relay, and use the ignition or some other ignition switched source to activate the relay coil. Trust me, tapping off of the ignition for 0.1 amp to switch a relay coil isn't going to affect anything.

Usually the radio is powered off of the switched ignition also, so therefore if you replaced the radio with an aftermarket radio (of even slightly higher current than stock) then the key fob would die. Tapping extra wires off the ignition wires would mean more current through the ignition circuit, which is the same as replacing the radio with a higher current one. There's your proof that the key fob failure myth is a crock of shit and doesn't actually exist.

Oh, I have a possible explanation... If shade tree installers are tapping off wires and running them close to the transponder stuff, maybe that is inducing a magnetic field that is messing something up.. That doesn't really make sense though, because you can't make a magnetic field without any current running through the wire, and there isn't any current running through the wire if the ignition is off. So again, I think it's people who don't know what they're doing messing things up.