Most recruiters are agency recruiters. They get paid a commission based on your first year's salary - usually around 20% and if you don't stay at company at least 3-6 months depending on the contract they sign with the employer, they don't get paid. They are theoretically interested in getting you the highest salary possible.[1]
Regardless, if you tell them your minimum salary and they know the hiring company won't possibly reach that salary, they won't waste the company's time.
[1] theoretically when someone is paid on a commission based on you getting the highest price, the incentives should be aligned, but studies show that in reality it doesn't work like that (https://www.nytimes.com/2005/02/20/business/yourmoney/why-a-...)