Also if you do not provide basic support the new immigrant YOU may be sued by the sponsored immigrants and by the agencies for the amount of benefits provided to sponsored immigrants. Income tax refunds (state/federal) can be attached, your wages can be attached, etc., etc. The I-864 has been declared a legally enforcable contact by federal courts. The really bad part is you are obligated to support the immigrant until the immigrant naturalizes, works for 10 years, leaves the US permanently, or dies. If you die your estate can be held liable for any obligations that arose before the support obligation ended. Now the real, real bad part. DIVORCE does not nullify the I-864 obligations.
Might appear to be unfair but I say that every week I do not win the lottery.
A la orden,
Gator