Treat (someone or oneself) to (something) verb phrase
To offer and pay for something as a present or as pleasure for someone.
After the university entrance exam, I decided to treat myself to a trip to Paris.
Let's eat out. I will treat you to lunch.
On the occasion of her birthday, she treated her friends to a round of drinks.
To pay the bill for something
Be interested in buying something
Something offers better value for your money.
To make a payment for something.
If you fall for someone's trick the first time then they are at fault.
Are you going to mess with me again? Fool me once, shame on you; fool me twice, shame on me.