Soup culture varies from country to country in Southeast Asia, but you're right, in general sipping form the bowl is no problem. Also, it's very common to lift a soup bowl from the table and bring it halfway to the mouth to take getting the last morsels with chopsticks more possible.

I know in some countries slurping soup is a sign of respect and that the soup is delicious. I will never adapt to violently slurping soup though. !ENGAGE 50