I'm talking about food from supermarkets. It's definitely more expensive. If you eat crappy street food, maybe it's cheaper. Unless they don't scam and overcharge you, as they like to do with stupid foreigners haha
When I was in Vietnam before covid, it was already more expensive than Thailand (except booze and cigarettes of course). Food in supermarkets is easily 50% more expensive. Fish, fruit, juice, milk etc. Clothes, electronics are more expensive too.
Again, the insurance trick works only with Bangkok Bank. The other ones don't offer this option. They call sell you insurance of course, but won't open an account for you.
Booze and cigarettes are cheaper, for sure. If you are a heavy drinker and smoker, you can save a lot. But almost everything else is more expensive - from food in supermarkets to clothes to electronics.