Interesting... Thanks for your speculation! They may well eliminate those "sweet spots", it's true... But I still think that focusing on them is to miss the point. FFP from an airline's point of view are a way of getting you to spend money with an airline in future. They are only disguised as a reward for travel already done. So why should LH care if someone has a shiny gold card? The cost is minimal- I notice TK have eliminated physical cards altogether, so LH can even do that if they want. And 4x per year SEN lounge plus a couple of entries to dingy flag carrier lounges in NAf ? A couple of bowls of potato salad (or of couscous if you're lucky) plus a few trips to the toilet are hardly going to cause huge expenditure. And if people do 4xNAf plus a bunch of economy flights, they'll be spending more money with LH anyway.

I sometimes wonder what's more important to people- that they themselves get lounge access or that others don't get lounge access....