i think because nowhere is 90 a speed limit, it is much worse than 30 over in say a 70 in a 40 situation, and will be viewed as such in court
i once had to sit in a car for 5 hours with an idiot friend with a sports car who thought it was oh so cool and clever to drive at over 100 all the way there, and seemed to think that because she hadnt crashed yet it was all ok (conveniently forgetting the few minor crashes she has had) and felt that all the little 'near misses' as she slammed on and weaved in an out of lanes etc, didnt count as bad driving because she hadnt hit anyone...
i was praying for a policeman or machine to catch her, to teach her a lesson.