This is a loaded question in so many ways. You may be confusing other genres like lounge and bossa nova with jazz. In general you'll find easy listening music, and smooth jazz is included in this. But I don't expect you'll hear other kinds of jazz like modal jazz, free jazz, jazz fusion, and so on.

Typically you want music that's quiet, low or mid tempo, free of vocals, and does not consist primarily of music made with synthesizers (as older people may find this to be a turnoff, even if it's peaceful music). I have a feeling that a good portion of this is (other than classical music, as mentioned in another comment) being categorized as "jazz" to you because you may not be familiar enough with a large variety of music.

Also I can give you a piece of advice. If you are in charge of creating a playlist at an upscale Italian restaurant in San Mateo, California, working part time minimum wage as a line cook, and your boss says, "Hey, you have long hair, you probably know a lot about music, right?" you should not choose your personal, pre-existing playlist that consists of every song in the entire Napalm Death discography that is under 60 seconds long. Just throwing in related life advice for OP and any other commenters.