Joyce,
I am a little confused. I know that if you look into doing the right thing and making sure you are legal in all respects, you can sometimes get bogged down when in reality, often there is a simple answer.
I had this with my business of Professional carpet cleaning following my investment in a £60,000+ 'Truck Mounted' cleaning unit. With environmental considerations and EU regulations there was a big question of where we were legally allowed to dump the waste water. Answers varied from, disposing of it onto grassland, down the customers toilet etc. Finally the official answer was to put it down the drain at the house where the job was being carried out, or take it home (Tank in the van) and empty down my own drain - simple!
There was also a similar dilemma regarding plastic fuel tank for the same machines. The only regulation published that referred to plastic fuel containers, was the standard Jerry Can type, which limited the capacity to 5 Litre. We carried 25 Litres. After months of searching, inquiring, like you are doing about your lifts. I finally got the answer that it was a grey area, in other words, never tested before, and that they had decided that as it was a reservoir required in order to fuel an on board machine then a 25 Litre plastic approved tank was okay.
The guist of what I am getting at, is, could it be that the answer to your problem turns be as simple. If you are not charging people for the pick up, then surely all you are doing is giving them lift and they then become your passengers. The lift is then not part of your business. They become your clients once they have booked in.
I know it may not be that simple, but then again it may?
Dave.