> A segment which comprises, by simple math, a full 15% of retail, customer service, and hospitality workers, who in turn make up a very large portion of the working poor, one of the least-well-represented interest groups in the US.

Questions around the math aside, in Australia for federal elections the polling booths are open from 08:00 through to 18:00 - and the process to hop in and vote is typically fast, at least compared to what we see on the news for USA elections.

In either case, it means the number of people who can't get to a polling booth during those 10 hours on the Saturday is relatively tiny. And, as you and parent noted, early / postal voting is a convenient, non-contentious, trusted option.