OP wrote:
"I used to be able to connect fine at this specific cafe previously as well, and then one day this problem just started happening. As I like to go to this place frequently, it's really getting in the way. "
"I assume there is some setting I inadvertently changed on my mac, but I don't know what it could be."
Perhaps it was a setting that THEY changed.
Have you tried asking at the cafe? Someone there must maintain the internet/routers, you should talk to him/her.
Also, Brian made a good suggestion above.
That is, create a NEW, "empty" account on your MacBook, for "test purposes only".
Log into it and see if anything changes on your end.
Does it? Can you connect ok using the test account?
Final thought:
You said above that your MacBook still works fine in OTHER cafes, and only has a problem at this particular one.
If you aren't able to resolve it to your satisfaction, I suggest that you consider "taking your business elsewhere" (seriously).