Takes2, unless they’ve changed the rules in the past few weeks, you’re wrong. I’ve shopped at Bingo and they’ve been happy to sell me stuff even though I’ve never given them any personal information. Bingo does have a free membership program that gets you better prices on a few items.
Moisha’s won’t let you use a credit card unless you “register.” I put it in quotes because the only information I had to give them was my phone number.
As regards the original topic, I get so few legitimate calls on my land line that I almost never answer unless I recognize the caller ID. And it’s not only frum Jews who get these calls. I’ve seen comments on websites like 800notes in which non-Jews complain about getting calls from Jewish charities.