I really think you are a bit irrational.
Can't wait 20 minutes for a Grab?, how much time did you spend flagging taxis in the street and trying to get a taxi at the taxi stand?
You have an armload of purchases from Centralworld but you don't want to pop for a taxi for 200 baht? How much did you spend in Centralworld?
When you were shopping in Centralworld did you apply the same kind of value for money analysis to your purchases?
Did you ultimately walk from Centralworld to your destination?
If all the taxis want 200 baht then that was the going rate wasn't it?
I know, you remember when it cost 5 cents to go to the movies but that was then, prices have gone up now.