Police cannot legally confiscate equipment just because you are sitting somewhere with it. Even if they suspect it is a wireless appliance, there would be no evidence you're doing anything illegal. Even if they think you are doing something illegal, they would have to come up with an actual law that they think you are even breaking. You would have to either voluntarily give your pineapple to them, or be arrested on a charge. Evidence seized illegally could only result in any future charges against you being thrown out immediately. Worst case scenario is you would get asked to leave private property.
Still, would be prudent to have an encrypted data partition, though.