Granted, the "nickel and diming" of hotline numbers (1900, 0900, etc) was nowhere as bad as today's cash shops, but a lot of us simply forgot they were always hungry for all our money

Here's a bunch other hotline ads for you to peruse - https://www.retromags.com/gallery/category/1729-telephone-hotlines/

PS: I never understood these american numbers that used letters, how were you supposed to know what was the actual number?

Your phones don't have letters on the buttons?

Long ago, before cell phones blew up how many numbers people used, American seven digit numbers were often referred to as a combination of letters and numbers. Below was a guide I how to translate the first three letters to a single word for numbers in Chicago

When each letter is in a different number, I can understand, but what about "TIPS", both P and S are on 7, so it'd be 8477?

That kind of thing was never used in Brazil, though part of that could be explained by telephones being state controlled up until 1990 or so, people could wait years to get a line.