Removed Tax Disc feel guilty when driving

Now the DVLA don't issue paper tax discs you don't have to display one. So when I cleaned the car this weekend I took it off and moved the National Trust car park sticker into it's place. Very weird but I felt as guilty as sin when I drove car today. It will be very strange seeing either no tax discs or expired ones as the changes kick in. Perhaps like in Eire we should have Insurance discs instead.