1. Depends how "dead" the dead of night would be! There are definitely security guards and cameras active after hours, and there may be gym trainers who have stayed late. (There may also be the Gym Leader. Sometimes you work late, sometimes you stay late to train....) There are usually also some strong Pokemon who make their homes there in the Gym.... of course, it may be possible to steal or catch those same Pokemon if you're very strong yourself.
2. No cash, but Badges and other rewards are kept at the Gym itself. They're stored in locked rooms and sometimes even locked safes after hours.
3. While the badges are real, they confer none of the perks that come with earning them honestly: you can't steal the Storm Badge and become able to Fly, for example! You could, however, absolutely use them to scam your way into/past places where (for example) a person is checking peoples' badges before admitting them. (This would not work at places like the Indigo Plateau gates, though, because those will run a full electronic background check.) If all you want is bragging rights or entry to a fan club, though, you might just get away with it!
no subject
2. No cash, but Badges and other rewards are kept at the Gym itself. They're stored in locked rooms and sometimes even locked safes after hours.
3. While the badges are real, they confer none of the perks that come with earning them honestly: you can't steal the Storm Badge and become able to Fly, for example! You could, however, absolutely use them to scam your way into/past places where (for example) a person is checking peoples' badges before admitting them. (This would not work at places like the Indigo Plateau gates, though, because those will run a full electronic background check.) If all you want is bragging rights or entry to a fan club, though, you might just get away with it!