ants - tenants

🐜An ant knocked on the door of a house.
The house owner opened the door.
"I want a place to stay," said the ant.
"I have a vacant room which you can occupy for free of cost," said the owner.
The ant went inside and occupied the vacant room.
After some days, the ant brought in another ant 🐜and requested the
owner, "Can you please allow this ant to stay with me?"
"Oh sure, you can do so without paying any rent," said the owner.
After some days the ant brought a 3rd 🐜ant and requested the owner
to allow it to stay with them.
The owner agreed to it without asking for any rent.
This went on as the 🐜ant brought in more and more ants and the owner agreed to let them stay without any rent.
One fine day, the ant brought in the  10th ant 🐜and requested the owner
to allow it to stay with them all.
The owner said,
"OK, you can all stay here but now you all need to pay rent."
Now the question is:
Why did the owner ask for rent when the 10th ant came in?
.
.
.🤔
Because they were now tenants!
🐜🐜🐜🐜🐜🐜🐜🐜🐜🐜
PS: I am also looking for the guy who sent me this!