why does Nick get so angry with Klipspringer and Wolfsheim?

I believe you're referring to Gatsby's funeral here, and the decision of both men to not attend. Klipspringer says he can't attend the funeral because he has a picnic to attend........ none-the-less, he has the time to pick up shoes at the house.......... As for Wolfshiem, Nick goes so far as to go and see him in person, and yet he still refuses to attend, not wanting to get mixed up in murders. What Nick sees in these men is the lack of morality in a group he'd consider "new money."