Got a story to tell you. I used to work at a roller rink a long time ago. Remember cheapskates were like $2.50 per person? That happened with this price and I was going to come in to work as floor guard. However, the manager forgot to show up to open up and people were complaining when they will open. I HAD to open up myself, unlock the doors, turn on lights, etc. I was only supposed to be maintenance only. Just clean and fix things. But I had to run the WHOLE place myself except for music because it was sponsored by a Christian radio station and their dj was playing music.
Since I was not allowed to go in the vault, I had no cash on hand for people. FIRST person had $20 bill on his hand and I apologize to him that I do not have $17.50 in change. I quickly told about first 20 guests who came in including that boy that they have $2.50 IN QUARTERS only. Sure enough, someone did, then built up a bunch of cash.. slowly I asked them exact 2.50 in paper money and quarters.. then the 5, then 10.. Then I had enough to give the first person who came in with the twenty the 17.50 change back to him.
So, it is necessary to give ones and fives to stores because more people these days are NOT counting the total of the bill themselves so they give larger money for a break of change. I admit I do that often because I would not know the total.
Yes, I see it often at thrift stores, gas stations, etc. They said in gas stations, they have way too much cash and they have to put in vault right away meaning a lot of ones and fives go in the vault.
People using cards today are making stores not able to have enough cash for customers with cash but also people using cards will want cash back. I have seen that happen. Not a great idea because they need to keep cash for customers paying in cash so they can get change back. That is why the shortage of ones and fives everywhere.