It's legal
A. A person shall not drive a motor vehicle at such a slow speed as to impede or block the normal and reasonable movement of traffic except when either of the following applies: 1. Reduced speed is necessary for safe operation or in compliance with law. 2. The reasonable flow of traffic exceeds the maximum safe operating speed of the lawfully operated implement of husbandry. Yeah, obstructing traffic to enter a parking lot is not legal.
Not an attorney just a coffee drinker here.
Thanks! Your answer is awaiting moderation.