Really I'm in two minds here.
On the one hand I don't consider it 'sneaky" to expire points per the published policy of the program. Surely at some point it is the responsibility of the member to be aware of this.
On the other hand though, they(QF) do not go out of their way to advertise this. Now, some have posted they do give you a warning in their monthly emails - but many skip those - and specially if an infrequent flyer gets these and isn't doing any travel they would probably trash it as not relevant to them at that point in time. Now is that the fault of QF? is it "sneaky" if they provide a written warning in their newsletter but it's not read by the recipient? I guess everyone's mileage will vary.
Certainly, as demonstrated, some programs are much better than others at informing you both on apps, or in emails or on the website of the program when you login. QF is poor at this (when I login I can see no place on the summary screen suggesting my points will expire if I have no further activity in 18 months - and that's poor). When I login to United, for example, I have an actual date of expiry right there under my balance. Even my poor eyesight can see this and it's clear.
I suppose I personally am in the camp that one should be aware of the published rules of such things. Others are more used to being spoon fed with reminders and warnings and stuff (and yes, when I get a text from the denist reminding me I have to go next week it's both good and bad !!!). I can see both sides of this, but I also think that at the end of the day we as members or users should take some responsibility to manage our own affairs.
QF should make it clearer though and it definitely seems a conscious decision to remove this information from the summary screen which i think is poor. Sure, they benefit from points spill, but I also imagine it's small amounts per month that are actually being expired. Anyone with a significant balance will be invested in what's going on with them and/or have activity enough, even if it's EDR or a bank account/CC linked or something.
my 8 cents