Yeah man. They actually asked me if my insurance covers test drives, I was like WT-F? Then they are like, "well we will have to call your insurance and have to have them fax us paperwork that says you can test drive cars and they are covered." I was like, "you can't be serious...isn't that the F__king reason you have insurance for?" They are like, "well...yeah, but just in case." I was trying to test drive a 5er about 2-3 years ago. I told them to shove their car up their ass and walked out of the dealership. Have NEVER been to a BMW dealership since.
MB on the other hand...I go there, and they walk right up and are like, "oh, are you finding everything ok?" I'm like, "well, this car just came out, I'm not that interested yet, but I would like to test drive it and get the feel of it for the future." The response is "Oh, that's unfortunate you're not buying yet, but sure I can let you test drive it, and you might change your mind." I've driven the w211 E, w221 S, SLK and ML like this.