What's a word for a person who buys random things just because they're on sale?

Recently, my dad bought headphones just because they were on sale. But, the thing is, none of us needed new headphones, he just got them for no other reason other than they were on sale. This isn't the first time he's done this either.

He's bought a bean bag game cause it was on sale, he's bought a futon even though we didn't need it and barely use it, he bought my mom a motorcycle that she never uses and probably only rode once, and much more.

I'm trying to think of a word for this cause I know he's not a minimalist when it comes to money because if he was then he wouldn't be buying all these random things.

So does anyone know a word for this? Please let me know! I'd like to have a word to describe my dad. That way when someone asks in the future, whether from a boss or something of the sort, I have a word prepared for it. Kinda like preparing for future questions about my family.

Persons of the sort you describe are called "shopping addicts" or "impulse buyers".

(Wikipedia) Shopping addiction is defined as the deficiency of impulse control which appears as the eagerness for constantly making new purchases of unnecessary or superfluous things. It is a concept similar to "oniomania", or "compulsive buying disorder", although these terms usually have a more clinical approach, related to a psychological individual disorder of impulse control.

(Wordhippo) What is another word for shopping addict?
One who shops compulsively

(FreeDictionary) impulse buying n. the buying of retail merchandise prompted by a whim on seeing the product displayed
impulse buyer n