Using the flexible pricing option, I see the nightly rate is rarely reflected in the price for multi-night stays

For a two night stay in China later this month, the price quoted per night for that 2-night stay is significantly higher than for either of the nights booked separately.

Is there any downside to booking the nights separately?

I recognise the two stays will be classified as a single stay for HH status-earning purposes, but does this mean the rate will be adjusted to reflect the higher price for a two night stay?