Apparently, some years ago ('50's or early '60's) the JW's had a convention in New York. In one of the local newspapers, it reported something to the effect that "they came into town with the 10 commandments and a 10-dollar bill, and didn't break either of them." This is hearsay on my part, but I have no reason not to believe it.
Once my JW ex-husband and I and an older sister ate at a local restaurant. The waitress was having a bad day, and the older sister said, "Don't leave her a sign of a tip!" I told him that waitresses are poor and may have children at home. Then I asked him, "Would you like it if you had to live on handouts from your customers? Don't you have a bad day sometimes?"
My experience with American JW's is that they are more tight-fisted with money than most other people.