Yes, and I suppose a lot of those high demand first year classes are big lectures. If they can get you to do those elsewhere, their proportion of “class size of 50+” or similar metrics decrease, which may help their rankings.
I suppose it could also allow them to admit students that fit their institutional priorities without having this show up. For example, maybe they want to admit more students who are full pay, but they also want to proclaim they are “need blind” for admission. This would allow them to do so because most “need blind” schools admit in tiny print that they are not need blind for transfers, and these students are technically transfers.