I am not sure about the 24 hour part but, yes. That is why we have all of our borrowers opt out of pre-screened offers prior to pulling their credit. We also do not include their phone numbers when we pull credit as well, just in case they fail to opt out.
If you have not opted out you are still getting credit card offers in the mail and other “pre-approved” offers. When you opt out you may also see a benefit in your credit score (some say they build in a buffer for people who are being bombarded by offers…assuming that these folks will be applying and adding more consumer borrowing ability.)
We also have never purchased these leads on principle.