Given the existing system, it's silly not to participate. It's not a case where a boycott would help, and by holding the patent you ensure that no one else uses it against you.
We all know that prior art can be missed when issuing a patent -- I'd assume having it already in the patent system makes that less likely to happen, and easier to deal with when it does happen.
A - Wouldn't they be protected due to f.lux being prior art? B - Would a competitor be able to get a patent on this in the first case? (due to A)