They were used in Atlantic City to test gaming operations before new casinos opened. Test periods or "Fun Nites" were held for a few hours, usually for 5 nights minimum. Play money and Fun Nite chips were used on the tables and cashier cages. NJ CCC and Gaming Enforcement officials would watch closely and conduct audits at the end of each night. On fun nights, players would purchase play money, with the proceeds going to a local charity. With the play money you would buy chips and play at the tables.

Real money was used in slots but like the tables, slot operations were watched closely and audited at the end of each test period.

Fun Nites used to be open to the public but Borgata and Revel were invitation only and used real money and rack chips.

Some casinos had custom fun nite chips made while others used generic chips. The generic chips you show were used at Showboat and Trump Taj Mahal. I was at both.