Can't they be sold on the site? I remember that, at the very beginning, I sold them right there—they would convert them to sats for you. I'm not sure if you're saying this out of ignorance or if the option has been unavailable for a while.
FreeBitco.in has always had a 1 satoshi difference between their price and the spot exchange rate. This might’ve made sense when the price was more than 100 sats per token, but at current prices you are getting 33% less than what they are worth. The only way to get a fair rate is to withdraw them and sell the tokens on an exchange, if you can find one where they are still listed. Since Binance isn’t an option for me, I’ve had to settle for their terrible rate when my tokens became unlocked.