Repeated sightings on business trip

As an avid 'people-watcher', a couple of my strangest coincidences have arisen due to me observing fellow travellers when on journeys. The most noteworthy occurred when I was travelling to a meeting in Brussels. I was passing time in Fiumicino (Rome) airport and a couple caught my eye. They appeared to be business colleagues but somehow were very distinctive and caught my eye as there also seemed to be a frisson between them and he was much younger. When I boarded my late-afternoon flight the same couple were sitting in business class near the front of the plane. We arrived in Brussels and as happens, fellow passengers of my flight were quickly lost in the airport throng. I thought no more about any of them. Using the public transport network I made my way to my hotel in the centre of Brussels to drop-off my bags before heading to find a restaurant to eat in. I set out with no plan of where to go and was feeling a little lonesome. After walking up and down the same streets several times and passing many different places which didn't appeal, I found myself drawn to a particular place which looked friendly and welcoming... (happened to be an Italian restaurant! How embarassing :-) ) - after being placed by the waiter I looked around me and realised that the couple from the plane were sat at a table opposite mine (they were on to dessert already so I hadn't subconsciously recognised them and followed them in!). That of all the restaurants in Brussels (and indeed that particular quarter near the Grande Place where there are hundreds all lined up next to each other), we were in the same one seemed a big coincidence. Next morning, guess who I spotted in the hotel lobby? The day went on, I had my meeting and then left in the evening, rushing straight back to the airport to go back to Rome. Low and behold, as I walked down the aisle of the plane, I saw the same couple again sitting some rows in front of me. They glanced knowingly at me too and I suddenly felt like they could perceive me to be some kind of very inept spy who had been following them round.