At the end of the day, the MSCs, in collaboration with their customers--the restaurants--are the ones who design these shops. Is the bar + restaurant visit a little distinctive, in ways that might raise suspicions that someone is a mystery shopper? Probably. But if the MSC and restaurant decide that's how they want the shops done, I'm not going to fret. I'll do what they ask, do my best to make it seem natural, and report what happens.
If the restaurant staff notice that people who hit both the bar and restaurant are disproportionately mystery shoppers and are a little more attentive than normal, so be it. If MSCs have an issue, they're welcome to pay for separate bar and restaurant shops.