This is an odd effect.
Antenna theory essentially states that the antenna must match the wavelength (be it whole number or fractions) .. and with a frequency of say 45MHz [average for most "non-IR remotes"], the wavelength is 6.67m (lamda = c / nu; where c = 3.0e8m/s and nu = 4.5e7s). The most efficient antenna tend to be: full wave, half wave and quarter wave antennae which means: 6.67m, 3.34m, 1.67m
Average human height happens to be 1.6m [5'6"] (which is the quarter-wave for 45MHz). Wow! So, using a human body, the ideal quarter-wave frequency is 45MHz.
*note to self*
*evil grin*
So the average human body _could_ act as a passive reflector ..