Wendy Treat waited in her car for five minutes to buy gas today.
She says that's what it takes to save money, but she has her limits.
"Sometimes if it's really, really bad then you just say, fine I don't need it today and I'll do it another day," said Treat.
Wendy buys her gas at the Costco in Chula Vista.
In San Diego, Costco is selling gas for $2.99. That's more than 50 cents cheaper than the county average.
"I would say I come here bout 95% of the time," said Berna Bauer. She says the lines move fast and it's worth the extra savings.
But how can Costco sell gas so much cheaper than other local stations?
"If I were to drop down that much I would be losing money," said Lori Hupp.
Her family owns the Bonita Point 76 station a few blocks from the Chula Vista Costco. On Wednesday, they sold regular for $3.67. That's 68 cents more than Costco.
Does the big box store sell their gas at a loss?
"They have to be," said Hupp. "I don't know how they could get it that cheap?"
But many drivers don't worry about how they are selling it that low; they just want to save money.
"I think it's great," said Cindy Hill.
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