Yes Ziploc bags can be reused multiple times before they wear out and should be thrown out.
When you use Ziploc bags you can reuse them several times by washing the Ziploc bags out and then drying them out.
I've used Ziploc bags over and over for around 2 years before they wore out enough to need replaced.
Most people just use the Ziploc bags one time and then throw them out after a single use which is wasteful.
As long as the Ziploc bag is in good condition the Ziploc bag can easily be washed out and used over and over again.
Throwing the Ziploc bags away after one use wastes not only resources but also wastes money and by reusing the Ziploc bags over and over as long as you can you save money as well as save the environment.
All those Ziploc bags take up a lot of space in the landfill.