The restaurants I've always worked at just seasoned steaks with salt and pepper. Of course, those commercial gas grills put out way more BTU's that a home grill can.
If we need to marinate a steak, we do it. We have a marinated London Broil on the menu right now, and they're marinated about 24 hours ahead of time.
Peace, Love, and Vegetable Rights!
Eat Meat and Save the Plants!