Foodies travel in herds—perhaps half-a-dozen strong—constantly "trying new places." There's a lot of potential for you to impress them and make your establishment one of their favorites!
You can't, however, rely on great food alone. While the quality of your product is obviously important, the food itself is often secondary compared to the what's happening around it.
The primary product of a restaurant/bar is atmosphere. You're selling fun, romance, excitement, convenience, expectation, entertainment, place to celebrate—or whatever it is that makes the guest experience unique to your venue.
Failing to acknowledge and act on this could mark the end of your business. The very best Chateaubriand in a cold, silent, brick room won't taste nearly as fine as a sloppy burger in a fun and friendly neighborhood pub.
Your music selection influences atmosphere immensely. The wrong music can lose you money; the right music can increases your profits.
Research suggests that music with a slower tempo increases the amount of time customers spend dining when compared to music with a fast tempo. Additionally, the same study says that "the music tempo was found to have a significant effect on money spent on both food and drink at the restaurant."
With this comes the need for balance. At your business's peak times, you may not want people lingering for a long time—but you certainly do when it's quiet. A small difference like this ultimately does impact your bottom line.
The right music for the right time is a valuable consideration.
Properly considered music focuses on your price point, your demographic, and the time of day. It influences how much your clientele will spend, how satisfied they will be with their purchases, and whether they'll return. Faster music in busy times results in higher turnover; slower music in relaxed times results in higher sales.
Specific playlists, targeted to your venue's demographic, increases customer loyalty and the amount they will spend. In an upscale environment, for example, classical music significantly increases the amount that people are willing to pay for their experience.
This is important since even a small increase/decrease can be the difference between profitability, breaking even, or actually losing money.