This reminds me of something the British actor Richard E. Grant (of Withnail and I fame) wrote about in his diaries that were published in the early nineties. He spent part of the eighties immersed in the Hollywood scene off the back of Withnail and met or hung out with a lot of very famous actors and musicians, about whom he tells various anecdotes. He spent time with people as famous as Madonna, Steve Martin, Bruce Willis and Demi Moore at their peak, and went out with them to events and eateries etc, and he made a very astute observation - that even major A-listers are perfectly capable of going out and blending into a crowd to some degree and remaining fairly undisturbed - if they want to. Some such as Madonna really don't want to, and he made the point that he observed them engineering hysteria around themselves through the way they behaved in public. He contrasted going to an event with Madonna, who dragged an entourage with her, dressed like a movie star and went up to a balcony and leaned, practically hung herself over it to hit a spotlight and get the crowd's attention away from the act onstage (her own backing singer trying to start a career), to Bruce and Demi whom he met in a queue to go see one of their own films, who didn't get mobbed at all because they just dressed and acted normally.
Markle follows the Madonna pattern far as I can see. Engineer the appearance of celebrity and hope for attention to follow you. The photographer who spoke about her before she married Harry said she behaved like an A-lister with her entourage of 12 and stupid diva antics when she was a nobody in the business. Dragging a carful of security around a safe place like Montecito where stars are ten a penny and nobody bothers them fits the profile of someone who desperately wants attention, NOT privacy.