Bottle liners?

Lauren • Had my sweet girl 02/22/20 - 5 weeks early due to rare genetic disorder💗 Had my handsome man 09/30/22 - 3 weeks early due to low birth weight💙

My sister and I were talking about if I had enough bottles (we received a couple sample bottles and 2 different brands at the shower: Dr browns and Avent) and the when I told her I only had 4 bottles with flow 1 nipple, she said that’s all she had when she had my nephew. So I asked her if she just constantly washed them and she said no because she had bottle liners.

I literally didn’t even know those existed until she said that😂

Is it worth it to get bottle liners, or should I just buy more bottles/nipples?