Yes, chargebacks will hurt your wallet. It’s one of the unfortunate sides of accepting financial transactions. Treat it as any business that accepts creditcard/online payments would. You have to factor in/budget for the risk of chargebacks.
That is one of the prices you pay for being able to take peoples money.
It also doesn’t hurt to have a mini terms and conditions statement on the page where you accept donations. This gives you a little leeway in the chargeback dispute process but is unfortunately not a cast-iron defence.
Here is a real Terms and Conditions from an ex-PayPal employee that they recommend you use at the location you accept your tips. Feel free to copy-and-paste, changing username to make it custom for you:
By clicking the “Tip” link and completing the PayPal/Stripe checkout process, you are agreeing to the Terms and Conditions as described on this page. You are confirming that you are 18 years of age or older and that you are the owner of the Paypal account/credit card being used. Minors wishing to tip username should have their parent or legal guardian perform the transaction on their behalf. A tip to twitch.tv/username is purely voluntary and does not entitle you to any form of benefits, advantages, special treatment, or the like from twitch.tv/username at the time a donation is received and going forward. While tipping does not entitle you to receive any type of benefits, you will receive loyalty points to spend within the twitch.tv/username channel as a way to say “thank you”. Tips are non-refundable. Chargebacks will be disputed unless agreed before hand.