Why does Margaery have such strong support from commoners after only being there for a short while?

Pavlovian conditioning.
During the War of Five Kings, King’s Landing was struck by an acute shortage of food. King’s Landing is the largest city in Westeros and as such, relies on food imports to sustain its people. During times of peace, food imports largely came from the Riverlands, the Vale and the Reach, all rich fertile regions close to King’s Landing.
But the war changed things dramatically.
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The Vale and the Reach both stopped sending food to the city. The Riverlands became a war torn disaster region. Stannis’ fleet’s control of Dragonstone meant that food could not be reliably imported from across the Narrow Sea.
The shortage of food caused tremendous hunger and misery through the whole city. People became angry and desperate, and many of them blamed Tyrion and the Lannisters in general for the situation.
Then Marjery came.
She came with wagons and wagons of food from the Reach. She gave the food out freely to the city’s hungry, food that just a month before her arrival had reached sky high prices. Wherever she was, there was ample food, and people went home with their bellies full.
She rode into town like a savior.
Nevermind that it was her family’s rebellion that cut off food supplies to the city in the first place. The commoners associated Marjery with food, and loved her for it.
She made an effort with the smallfolk, always. The Tyrells brought food to a starving city, and Marjery made sure to spend time in the city talking to the smallfolk, listening to them, playing with the children.
Whether Marjery actually cared about them or not is irrelevant. She made a point of at least acting like she cared. She didn’t hold up in the castle and ignore them the way Cersi and Joffrey did, she went out, met them, spoke to them, fed them, played with their children.
Whether she actually cared or not, she made sure the smallfolk saw her as caring for them. That’s why she was so popular and had such strong support from them.
#gameofthrones #housetyrell #margaerytyrell #houselannister #kingslanding

[@truetory6231]

Margaery came to King's Landing with food, Daenerys came with an army of Dothraki and unsullied not to mention a dragon that roasted everything

[@paulsarnik8506]

Just ask Bronn about sieges🤷🏼‍♂️. 🤓😎✌🏼