There is a big difference between a criminal background check and a security clearence. When a young guy I know was being considered for a job for a Senator who served on the Senate Foreign Relations Committee, agents interviewed his parents' neighbors! No med school will go to that level of detail.
No one is obligated to list all employment on the application. That said, it is wise to account for large chunks of time as it is taken into consideration how busy you were during college -- all things being equal, the person with an identical record plus x hrs/wk of employment during the academic year will be considered stronger than the one with the same record & no employment.
Is prior experience as a stripper/dancer an automatic exclusion for med school? Some of you are acting as if it is or should be. 😕 On what basis would you exclude from admission a person who worked in a legal occupation? What if an applicant had worked in a slaughterhouse? Should that be left off the application in case some of the adcom members are morally opposed to killing animals for food? What about working as an employee of an abortion clinic? Where do you stop in scrubbing your application of anything that might offend?
If you didn't want to list dancer, you could list it as "employee" and leave the description as "worked part-time during the academic year and full-time during breaks to defray the cost of my education". That's all the detail that is absolutely required. If the name of the place is "The Gentlemen's Club" or "The Sugar Shack" the adcom can draw their own conclusions.
.
