I doubt the game is specifically making these rolls less random than normal, but I do agree that spending re-rolls to get the same boons offered again is not fun. While I understand that RNG is part of the game and genre, if there is a limited re-roll mechanic in the game, it would be great if it could make at least some effort to avoid re-offering the same ones (when possible).

I understand there are some technical complexities here when not all boons have equal probability, and there is the additional element of rarity involved, but even a naive implementation of hidden internal re-rolling a couple of times to make duplicates less like would be an improvement.

(I'd also like to reiterate my earlier suggestion that it would be great if the list of available boons in game could be filtered/sorted to show only the ones that can be offered. It would also help the decision whether to spend a re-roll if one could quickly see what the possible boons that you could be offered right now are.)