Depending on where you are in UK - ferries can make life easier
Coming from Aberdeenshire - it makes sense to take Hull-Zeebrugge ferry or Newcastle-Amsterdam
since Aberdeen to Hull is 425miles - approx 8-9hrs drive with breaks
going onto Dover etc would be 645miles 11-12hrs - which is a massive killer to do in the day, and you would maybe need to stay over somewhere before crossing the channel, or as soon as you arrive in France.
so ferry works well for us, as its a easier days drive and saves a couple hundred miles and driving round M25!, then overnight on ferry, and arrive in Europe the following morning.
and using Avios it costs little or nothing!