You are probably referring to LibreOffice and the App Store price is explained here:I found out the other day, OffceLibre, a well-known freeWare is only free if you download it directly from the developer's website, but Apple complains, "u didn't download it from our appstore" $8.95, so we can't run it for you for security reason... yeah right. Tim Cook, the master of nickel and dime.
“These versions are free software (as in open source) but there's a small charge to cover the effort of putting software in the app stores, and to help develop the software (and build our communities).”
https://www.libreoffice.org/download/libreoffice-from-microsoft-and-mac-app-stores/