I had to look it up myself. No good just googling "freeze peaches", you find a lot of pages on how to actually freeze peaches. It's a good homophone though: free-zpeaches. It's some kind of reddit thing... I've only been to reddit like 3 times so I don't know that bit of culture. My dad used to test speech recognition software by saying "It's hard to wreck a nice beach." A pretty cool homophone. Sorry -- tangent. I'm prone to those.
I'm new from Reddit (switched now because I learned about it and liked it better, not because I'm part of the radical groups), and I've never heard of the 'free peaches' thing before. I'm pretty sure it's generally restricted to the more unwelcoming subreddits that are dedicated to shaming and hating specific groups.