Our local McDs is not doing this but I can understand why an owner/operator might.
Like a lot of people, I worked in fast food for a period of time. It was not uncommon for people (usually teenaged guys for some reason) to order their food and, after picking it up, empty the ketchup bin of ketchup packs. After several incidents where the store manager actually WATCHED a person pick up the ketchup bin and dump the entire contents into their sack, he made it where only employees could give out ketchup packs. I don't think it ever crossed his mind to CHARGE for them however.