Using a fast food chain that is located in both the Philippines and the US, let's look at the cost of living. A 1 piece chicken plus a side of Jolly Spaghetti is 4.83 times more expensive in the US than in the PH (₱175 vs USD$13.49). The 6 piece plus Jolly Spaghetti is 3.43 times more expensive in the US than in the PH (₱805 vs USD$43.99). [The 1 piece in the PH includes a drink and the 6 piece in the US includes 3 pies, which muddies the math a bit.] 

When looking at the market rates in both countries for the same job at Jollibee, we don't see salaries that are 4.83 or 3.43 times higher in the US because we must also take into account the availability of people who want to be a front-line worker at Jollibee. In the Philippines, Jollibee has to pay ₱90 per hour in the National Capital Region and ₱50 per hour in the provincials to attract enough people to fill the jobs in each restaurant. In the US, Jollibee has to pay USD$15 per hour to attract enough workers. [Note that some states and cities have a higher minimum wage, which forces Jollibee to pay USD$20 per hour in some locations.] That means that Jollibee must pay a front-line employee in the US 18.8 times more than a provincial employee and 9.44 times more than an NCR employee for the same job. 

This example shows that the supply and demand for talent (along with some government rules around minimum wages) is a stronger economic force than the cost of living when companies are determining rates of pay. The minimum wage in the US is lower in most places than what Jollibee is forced to pay in order to attract new employees. While in the PH, they don't have to pay as much of a premium over the minimum wage to attract candidates for open jobs.

I know some of you are trying to do the extra math, so here it is:

• A front-line Jollibee employee in the PH must work 2 (NCR) to 4 (provincials) hours to afford the C3 1-pc with Jolly Spaghetti or 9 (NCR) to 16 (provincials) hours to afford the Family Super Meal B 6-pc with Jolly Spaghetti.
• A front-line Jollibee employee in most parts of the US much work 1 hour to afford the Perfect Pairs 1-pc with Jolly Spaghetti or 3 hours to afford the Bucket Treats 6-pc plus Jolly Spaghetti plus 3 Pies.