My two penn'orth on this from the perspective of a regular solitary business traveller:
1. How to I go to the buffet without loosing my seat / return my luggage trolley ditto
2. How do I go to the loo without having my luggage stolen
I know it's not considered very British to do this, but I have to say that the simple expedient of speaking to a nearby passenger is usually enough so solve this dilemma in my experience. "I'm just slipping along to the buffet, would you mind keeping an eye on my seat please?"
(I always say buffet even if going to the loo - and I also take my wallet and phone with me too)
3. How do I "note my table number and order food at the bar" ... I come back to my table, and someone else has grabbed it
I have to say, I detest this approach to "service" and if faced with it, I withdraw to find somewhere else to eat. I marginally prefer the approach where they present you with a wooden spoon with a number on it and expect the waitress or waiter to come find you. But generally, I dislike being referred to by number and would rather eat somewhere a little less impersonal if possible.
4. Why am I always given the pokey little room / table tucked away around the corner
Not wishing to make you feel at all paranoid Graham, but I have to confess I'm completely unaware of this ever having happened to me! Maybe thought that's as a result though of my response to (3) (above)
5. Why - when I am staying a a business hotel primarily intended for business travellers - do they offer "two for the price of one" meals in the attached restaurant - I find it a slap in the face (it's a good chat-up line - 'are you alone too - would you like a free meal' ...)
6. I can sometimes buy a "groupsave" ticket ... but I can't buy a "singlesave"
Fair point, but one can't really blame a company for trying to encourage business. Their hope is presumably that next time, you will bring a colleague and thus increase their income.
7. Why is it when I go our for a walk with someone, no-one bats an eyelid, but walking alone I can be looked on with suspicion, or be asked if I am contemplating suicide when I'm just admiring the beautiful suspension bridge, and the view of the road far below
Again, sorry if this induces paranoia, Graham, but I have to say I have never felt or been placed under suspicion when walking out alone - or not in this country anyway. Admittedly I've had odd looks in America, but that's usually because everyone else gets in the car and drives even to cross the road!