That quarter was painted by a vending company, maybe with nail polish. When a bar owner used them in the jukebox, they were given back at cash out time, not split with machine owner. Allowed them to keep the music going when patrons weren’t playing the jukebox. My former business partner worked for his uncle’s vending company. I would go with him to cash out the bars, restaurants & bowling alleys to meet the owners. I was an insurance agent and we specialized in them. Most were happy to get another insurance quote as their premiums are very high. So were the commissions
Yep, my experience is that bars would paint a certain amount of quarters with red finger nail polish and give them to customers to play the Juke Box. When the Juke Box coins were emptied, the red ones went back into a special slot or box to repeat the purpose. Used to be common, but not any more.