As to her motivation? Re-read your question and ask yourself how much trust you'd place in someone reporting to you with that level of respect for your position. (I don't know you or her, but you're not helping your position if you bring that attitude in to work)
My manager also comes round to check we are all in by 9:30am as we can come in between 8am and 9:30. I'd be peeved if she didn't as I don't appreciate people abusing the system and swanning in at 10am which is what was happening at one point.
Whickerman, I am beyond reproach on the matter, I object to the involvement of other staff members being asked questions which should be directed to me. As for an attitude..........you don't know me, so please don't make sweeping statements......