Is there more of a chance, or a reason why you would ever want to join the Cult in Miskatonic Horror?

Ever when the encounter comes up no one ever wants to take the membership. Have other people seen the same thing? Or am I missing something?

As to the chances: not much, but some. There are a bunch more encounters that let you join the Cult, and there's a skill that gives you the Membership. In terms of whether you'd want to, the new encounters are generally positive enough that it's actually a good idea to get a Membership. Most of them are both positive and negative, with a reward being offered for a drawback (the drawback generally being Corruption or loss of Stamina/Sanity), and many of these are optional. I think I can safely say that, assuming you're not drowning in Corrution, having a Cult Encounter is safer than having an encounter at the Woods, Unvisited Isle, or Black Cave. The worst of the new encounters follow the same template: you either choose another investigator to gain a Cult Membership and a Corruption card, or you suffer some penalty. What this means is that, although the chance of joining the cult is still not that great, one person joining likely means a bunch of others do as well.

If available I would join for 2 reasons:

1. I rarely get to read cult encounter or corruption cards (and do not look at new components out of game)

2. The frequency with which i draw "A gate opens!" on the relevant locations is sick enough to try and avoid or at least minimize.