Oh my goodness, what a wonderful thread.
Everything, for my parents, is "a bit complicated". Yes, that's because they MAKE it complicated by having to plan every second of the day, every bite eaten, every mile travelled, and make about nine thousand contingency plans in case of X, Y or Z. Life has moved on now - shops are always open, you've always got your mobile, Google exists. But deciding to "play it by ear" is akin to suggesting a family game of Russian roulette.
We've booked a self-catering cottage for later in the year and my parents started to worry about what we'd do about eating. "Ooh, if we're only allowed in at 5pm it's a bit late for the shops but we won't be able to carry stuff with all our luggage..."
Me: "We'll do a Tesco order for the evening we arrived. Bring enough to give DCs their dinner then it can arrive in time for us to cook ours."
DPs: "Ooh, sounds a bit risky... what if they turn up early before we arrive?"
Me: "They're not allowed to just do that, or if they do they have to com back within your time slot if you ask."
DPs: "True, but they might be late..."
Me: "Then we'll either nip to the local shops or get a takeaway."
DPs: "What if there's a substitution in the order?"
Me: 
They get an Ocado order every week. They're both retired. They're always in all afternoon but it's like the world ends if Mr Ocado is five seconds outside the timeslot or even turns up towards the latter half of the timeslot!
They will also never just ring up a company about anything but will fret over it for days. Once we were on a train home from my grandmother's when it broke down and they realised they'd be late for the Ocado order. (Are you sensing a theme?!) They fretted over it and decided they'd just have to not have any shopping that week and go to Sainsbury's on the high street tomorrow.
At this point I snapped, rang Ocado up, and pushed the delivery slot back two hours. No problem. But they were totally amazed that they could do that. They'll never ask anything unless they know the answer already, whereas I think it's literally the helpline's job to try and help me.
Phew, that was cathartic!