An obvious reason for the involvement of so many Roman Catholics in the occult is the fact that, having no assurance of salvation [1] through Christ alone, they look to many other sources for help in getting to heaven. The Council of Trent made it a mortal sin for anyone to claim assurance of heaven:
“If anyone says that he will for certain, with an absolute and infallible certainty, have that great gift of perseverance even to the end, unless he shall have learned this by a special revelation, let him be anathema.”
Links:
[1] https://www.thebereancall.org/taxonomy/term/57/salvation