Hmm, I didn't know that about the Beatles. I mean, I assumed they learned covers when they formed (like most bands), but didn't know they gigged as a "cover" band for a while. Interesting!
I see what you mean, and it may simply be a matter of geography. In Boston, if you want to see live original music, you DON'T want to hear covers; the people at the show are people who (for better or for worse) pride themselves on discovering new music. People who want to just go out with friends and have a good time with a live band have plenty of places to go. In a more rural setting, when one band plays the whole night to a very diverse audience, playing covers absolutely makes sense. When you have 35 minutes to play in front of a high music-IQ/hipster crowd, you'd better not play more than one cover (and it better be a fairly large departure from the original song!) Our music is targeted at a very specific audience, and to make the most of our time/effort/cash, we limit ourselves to playing gigs where the audience is, essentially, hipsters. Its a simply targeted marketing approach.
This is a great thead!