Because Rome was infamous at stealing cultures faiths, destroying the people and then erecting their new temple in Rome to their gods claiming the god or godess no longer loved the people by their defeat(early racketeering logic). They would become that cultures new religious authority. This is called the 2 horn (power) system whereby political power hid behind the religious authority collected taxes (tithes) with less insurrection. This is why they symboled The devil as the scarlet colored 2 horn beast cause Rome's color red and 2 horn system and it was a way to convey the symbolism without suspicion by the authority they were blasting on.
The one world religion Rome was gathering under their tax collecting power hungry authority had to appease all cultures traditions. Baal's father was Dagon the fishman god where the ancient tablets show tinsel trees and priests dressed in fish costumes with fishead hats.
So even today the Church wears fishead hats called mitres and wear scales on their robes and the Pope even wears the fishman god ring and they offer gifts under this tinsel tree on Baal's Dec 25th birthday.

When Dagon became out of favor the dying son Baal surpassed his father, when Baal was refused by Jews, the dying son of baal in mythology is called MORNING STAR
(rev 22:16 Jesus is made Baal's son), surpasses his father Baal on the throne.
-(Dying god mythology of the Canaanites).
Rome had to many Jewish Revolts, they thus did what they did to many cultures as mentioned above, creating a new temple to try and get Jews to worship Baal under the guise of a Jewish image for the same Baal harvest scam.