Why do bubble plate columns use a dephlegmator

[tarz]

Hello!

I´ve been thinking about bubble plate designs alot lately but I can´t wrap my head around one thing. It seems that all the bubble plate columns out there use a dephlegmator as the reflux condenser at the top and thus making the entire still essentially a CM still. CM stills are not fun (based on experience and the feedback on this forum) that´s why I´ve built myself a LM reflux still with the column being SPP packed.

However I can´t help but wonder why is that we are (mostly) using a CM setup(dephlegmator) when we could use for example a LM setup on top of the bubble plate column.

To illustrate my question
As-Is the popular (the dephlegmator variation)

CM Bubble.png

Alternative (LM variation)

LM bubble.png