While in Chapel Hill for 7 years, I averaged 40 moved from end of April to end of August. Yes that is 2-3 per week (coming in or going out) during those 4 months. Sometimes we'd go from one to the next to the next in an evening8ng or on a Saturday. It was literally everyone helping everyone else (for the most part). We had 20+ families per year turn over in our ward alone, plus two other wards friends and students were in. The rest of the year was quiet, you are right.
It has slowed in the 5 years since, but I still am at pretty much every one. I hate when I move, so I figure help is appreciated. And I get to take my older kids to let them serve.