Just add it to your ToS and website in a visible place, just like @NeuroticFish suggest keep everything transparent as possible.

As for now, the fee is still small, but what if the price will rise 10x? Everything is possible and I think devs have to rethink the fee strategy one more time and make an update.

The fee subject comes back as boomerang even in this thread, so it can be considered as a problem which only will grow if not changed on time.

Just my honest opinion and you know that I was also surprised by the fees a few weeks ago, despite, I use the GOLD token from few months and thought that I know everything about it.