MCP1703 quiescent current is very high
It sounds like you didn't connect an output capacitor when measuring the \$I_q\$.

From the first page of the datasheet, this regulator is "Stable with 1.0 µF to 22 µF Ceramic Output Capacitance". This implies it might not be stable without an output capacitor. 

If you connect it in an unstable configuration, it could oscillate, leading to much higher \$I_q\$ than expected or specified. 

As pointed out in comments, an input capacitor is also required to match the \$I_q\$ test conditions. Whether this actually has an important effect probably depends what kind of power source you use and how long are the wires connecting it to your device under test.