I feel like this is twisting numbers. The fact that 60% are "impuls buys" doesn't mean you are "tricked into buying more". If someone is renovating or moving, then they might go to Ikea to find a new bed or a new sofa, and then find they also need a sofa table, or bed table that they had not planned to buy. This is typically what we do, we don't make a full list of what we need ahead of time, we know some major parts, and then we browse and pick up more things we need. That might mean that 60% of what we buy wasn't "planned" but we weren't tricked into buying more stuff, we just figured out what we wanted along the way.

Naturally this makes the layout of Ikea important, because if you never go through the lighting department, you're not going to remember that you'd actually been wanting a desklamp and pick one out. But this isn't some sort of clever psychological hack thats tricking you into buying a lamp you don't need.