thank you for the quick answer, however this is not true that any
resonant of the 1/4 wave length will give the same performance like the
normal 1/4 wave length antenna because for longer antennas the current
that runs through the antenna will start from the 1/4 wavelength of the
antenna and will go up as well as down with an opposite phase thus
decreasing the total current of the antenna.

If you can think of another reason way they build such antennas I will
be happy to know

Thanks again
Tomer