I fly LHR-BRU-LHR about every other week and noticed this trend as well.

Also noticed there's a correlation between being a queue jumper, being rude to cabin crew and other passengers and failing to comply with standard safety instructions.

Unfortunately those people are flying on tickets paid with our taxes which adds extra salt to the wound.

But I don't really mind, it's 45 minutes and I (usually) enjoy that flight.