As tempting as it seems to wear tennis shoes with your tux, don't do it. I think it looks ridiculous. If you're 14 years old, maybe give it a shot. In general, don't portray anything that says 'I'm too cool and I don't care.
These evils I deserve, and more. . . . Justly, yet despair not of his final pardon, Whose ear is ever open, and his eye Gracious to re-admit the suppliant.