Slow Hitch-hiking?

It has been reported (https://www.theguardian.com/environment/2019/oct/23/snail-fail-australia-turns-back-mercedes-benz-cars-after-escargot-cargo-found ) that the Australian authorities have sent 900 luxury Mercedes cars back to their country of origin as some were found to be carrying Heath snails (Xerolenta obvia). Given Australia's past problems with biosecurity, the Department of Agriculture was keen not to risk this previously never before detected alien entering the country. The snail eats cereal crops and fruit trees and carries a range of parasites and fungal spores.