Try pricing out physical switches at your local electronics shop sometime. How much does say, 20 or 30 of them cost? How much a 7" touch-screen LCD cost? Then

Try pricing out physical switches at your local electronics shop sometime. How much does say, 20 or 30 of them cost? How much a 7" touch-screen LCD cost? Then consider how long it takes to wire up and install the LCD versus 20-30 switches (plus mounting brackets, plus functional testing etc.)