What American customs upset Mrs. Dutta in her day-to-day life in the novel, Mrs. Dutta Writes a Letter?

There are some American customs that Mrs. Dutta cannot understand. Shyamoli becomes frustrated when her mother-in-law throws out uneaten food, but saving leftover food is a practice that conflicts with Mrs. Dutta's Hindu belief about not saving contaminated food. Mrs. Dutta also does not condone her grandchildren's behavior toward their parents and is horrified when Shyamoli addresses Sagar by his first name and asks him to fold laundry—especially since the laundry includes Mrs. Dutta's underclothes. As a result, she volunteers to wash the laundry but is terrified of the washing machine and hand washes them instead.