Here is something to consider. Your driving the company van on the 30 minute no pay time. You get in a accident and have injuries. What insurance is covering you? Not workman's comp. your not on the clock. Not the auto insurance because you can't use the company van for personal use and since your not on the clock it is considered personal use per federal laws. It comes down to your personal medical insurance with your deductable. Also could your employer sue you for using the van for personal use and getting in a accident? Most likely for lost revenues from the van being out of service.
Ask around to some of the other service industries and see if they get payed for travel time. Most of them do get paid. If the customer is getting billed for the time the tech is getting paid.