Kayla,
While I do understand [and sympathize] with your motivation for reassuring clientele that giving up a drivers license isn't going to jeopardize ones anonymity, it should be recognized that there certainly are repercussions that *could* arise as a result of having your identity on file at an MP.
That said; there has always been some degree of risk of running into LE if you frequent MP's. If you [for one reason or another] can't tolerate this risk, than you shouldn't be going.
Here's a pretty good general rule to follow if you're seriously concerned about running into repercussions with LE: You're degree of risk increases proportionately by the reputation the MP (which includes the MPA's within the MP) for providing/engaging in services/activities which are beyond a level of tolerance (I'm sure most of you know what that level is). In-other-words: if you're favourite MPA(s) are providing you services that you think are special to you (or a select few), think again. To be bold; if you're gettin' it, LE knows about it, and you need to asses your own risk accordingly.
Here's my final thought on the licence deal...
I'm not 100% sure if I'm ready to hand over my identify to an MP. However, if I am going to other (well known) MP's that offer services beyond the norm (which I never do ;-)), LE probably has my plate number via survalence anyway (however, I always borrow my boss's car ;-)).
KKarn/