I personally see live as a completely different animal and prefer it to be a bit more raw (not to be confused with muddy or indecipherable) but in the studio, you can add layers, and use as many amps as you want, change snares and snare tunings for each song, etc.... live...not so much. You take what sounds best as a whole, make sure the amp EQ sounds good as a whole and not just on their own. I would not object to paying to some tracks live, such as keys... actually I will be doing that since my singer (who is also our part time keyboard player) is now full time singer/bassist....he's not Geddy Lee, so for the few hammond organ parts, we'll just play with tracks (and our drummer to a click). But trying to replicate all the layers and the exact tone etc, is not only nearly impossible, but it's not really needed. People come to shows to be entertained, not hear the CD exactly as the one they purchased IMO.
It seems for me, I am on completely opposite ends of the spectrum from myself between studio and live. In the studio, I use lots of different amps, VSTs of amps, compressors, reverb, delay, flanger, wah, Lots of shit. But live, I will carry with me amp, guitars, flanger, tuner, and I have played shows just straight into my amp before....some of my songs seem to call for that live. I can get away with it being polished and such in the studio, but live it just needs a little extra grit to it, take away the flanger, make it pushed instead of clean, etc.