Sure they do... Particularly if you live in Florida or California you can easily grow passion fruit. It's a pretty vine with gorgeous very unusual flowers... But a lot of the plants sold have been hybridized for the flowers not the fruit, make sure you get a good fruiting variety if you want to try and grow them.
The fruit are round and hard when ripe and are usually purple*, when split open, there are hundreds of little seeds that look and feel like tadpole eggs... The juice comes from the little jelly like sacks around the eggs. You can eat then as is, or use in cooking or as you've discovered, yummy juice drinks. There's not much juice in a single passion fruit, but it's strong, and is usually diluted for drinks. (see attached pic)
*most common variety you'll see here in the states.