Read fnords post and try and understand why are we asking ourselves these questions and you will become a better player because of it.

Also like d0zer said implied odds is huge here. Even if we are getting shitty odds v the initial bettor the fact that this goes multiway from street to street a huge amount(passive opponents etc.) and the fact that anytime we bink our flush or we bink our flush when someone has a straight/two pair/trips/overpair they can't fold with a fd or basically any hand that pays us off is HUGE.