My habit is to switch cards often and I have a stock of them available in
different sizes from 1 Gb to 16 Gbs. My habit is to shoot lots so they fill
up quickly. I have a 40 GB external drive that copies the cards without a
computer. It has its own card slots. So removing the card is just second
nature. I never think about connecting the camera directly and fiddling with
cables. I don't even carry one with me.

However, my wife learned that it is better to connect the camera the hard
way. She left her 4 GB card in a store re[rint machine and when she
remembered, someone had walked off with it and her holiday pictures. She
will use the camera next time.

Both methods work. It depends on your habits. Each has its advantages and
disadvantages. I don't think that wear and tear on the camera is a big
issue. You are more likely to break the camera in other ways than sliding
the card in and out as there is no mechanism to wear out, unless you count
opening the compartment itself and in my case the usb port is inside the
same compartment.