Do I Have to Give My Address to Enter a Giveaway?
Some details are genuinely necessary and others are collected because you will hand them over. The dividing line is what the company running it needs to award the prize and prove eligibility.
Reasonable to ask at entry
An email address so you can be contacted, a name, and a state or postal code, because eligibility is territorial and some states are excluded for legal reasons. A physical address is reasonable where the prize is a physical object.
Reasonable only at claim
A full address, date of birth and a Social Security number for tax reporting belong at the point you have actually won a prize of $600 or more, not at entry. A form asking for a Social Security number to enter is not a sweepstakes entry form.
Never reasonable
Card numbers, bank details, sign-in credentials, or a photograph of an identity document sent to a personal email address. If any of these appear, stop, and do not treat a claimed prize as a reason to continue.