Yeah, Reg E doesn't care about us
However, recovery of funds is not impossible, just very unlikely. Both Visa and MasterCard have compliance rights for mis-matched signature, but you have to recover the lost card and prove that the signature is different - specifically the last name on the sales draft is not the same last name on the card. There are other requirements as well, detailed under the appropriate compliance citation.
If the perp signs the draft with the same name as the name on the card, there is nothing you can do even with the recovered card. Merchants are not signature experts.