What, precisely, do they expect to happen with drunk people who want to get home?

If pubs are happy to serve drunk people, but trains aren't happy to carry them, doesn't this just mean that if the rule is enforced on trains, there will be a bunch of drunk people with no way home stuck outside a closed station until morning?

Or do they assume that everyone out drinking will either moderate themselves accordingly, or else happen to have the money for a sudden taxi journey at midnight between Edinburgh and Glasgow or hotel room?