Its pretty much a social institution here. It's strengthens community bonds. Seriously, if crucifying yourself and taking on the imaginary burden of a christ-like figure(in this case the original christ himself), doesn't strengthen ties I don't know what will.
It doesn't feel stupid to me though. Like most traditions and customs, even stupid ones, if you were born in the culture that made them up, its feels natural and "right."
You wouldn't make fun of the slave driving culture of Japan, right? If a country that has the social phenomena of "suicide by over work", isn't ridiculed, I don't know why'd you'd make fun of this particular aspect of filipino culture, considering that there are far worse cultural aspects here in the Philippines. Take for example, a representative of the filipino tribal nature, our former President Erap who funneled the entire country's money into his barrangay(equivalent of a town) which pretty much screwed an entire country so his "tribe" could get a leg up.