273 passengers on BA's Gatwick to Cancun flight yesterday, one of a handful of flights to a destination without restrictions on people from the UK, on the first day of Tier 4 restrictions that cover more or less the entire catchment area.
Given that Mexico isn't even on the 'travel corridor' list, and I doubt many of those 273 passengers were heading off for important business matters, I think both the appetite for travel and the nonchalance for these daft travel bans is fairly plain to see.