Hey Phantom, I totally get this show not being everybody's taste! But it remains one of my favorite shows and I'd like to offer my thoughts...
"I did not get why it was so funny that two towns had similar sounding names."
I think it's just phonetically comical. They could have tried to illustrate the cultural differences between the Egyptians and the Israelis in so many more serious, even sad ways, but they leave it to a a simple pronunciation issue between two towns that you have to admit sound uncannily similar. That's just funny, to me at least! (Also, look to the lyrics of "Welcome to Nowhere" for how adroitly Yazbek exploits this joke.) I think it's also a brilliant trick that they use this joke to set aside most of the explicit questions of culture and language by the end of the second scene, leaving the rest of the show to feel completely and entirely human.
"I did not get why the woman who owned/ran the cafe hyad all this time to just hang out and chill with this stranger, and why she seemed absolutely enamored with his dull stories."
Your issue here also ties in with the telephone guy standing in front of the telephone for 90% of the show, and I think is exactly why this show just is or isn't for some people. No character's story in The Band's Visit is objectively or individually that interesting, yes. But for me, the point of the show is that this one night between these two groups of people (which, yes, wasn't very important in the grand scheme of things) evinced all these beautiful moments of self-understanding and the simple act of being heard, felt, understood by another human being. Part of why I love the show is that it does such a brilliant job in creating these gorgeous moments of relationship in staging and music—but it doesn't all end up with a powerful "let's all be friends" message like you say you expected. As Dina herself sings, "And I don't know what I feel / And I don't know what I know / All I know is I feel something different." It isn't a piece of theatre where there's a message to take home because of the band's visit. It simply creates these subtle, beautiful (and I'd also say transcendent) moments that would never, ever happened to these characters without this "unimportant" evening. For me, that's what made it so transporting and beautiful and fleeting and human and real.
Just my two cents! (But for what it's worth, the song at the roller rink was an earworm for me too for a few days, ha!)