This explanation would not be valid even if those people who are not reminded of their own excess purchasing power – if in fact they have any such power – when they see such a logo nonetheless tip more in such trays.
我自己将它直译过来是:即使是那些未被告知他们自己所有的超额购买力(如果事实上他们真的具有这种能力)的人在看到标签时会在盘子里支付更多的小费,这个解释也不能证明是有效的。
有点被绕糊涂了。。。求高人指点迷津!