Unusual Venting

I saw this in an attic the other day and it seemed unusual to me. This home is less than 10 years old and had 2 furnaces. The upstairs furnace is in a closet on the upper level. Any thoughts why these vent lines would not extend above the roofline?

Thanks in advance


Looks like bath fan venting that terminates in the attic. Builders do not want to pay the extra $50.00 to have them terminated out the roof.

Combustion air supply?

Looks a little small for combustion air. That is typically 6".

Why have them terminate at the roof anyways when you can go out the soffit.