I've noticed the thining out of the bottle on the bottom of Fanta recently. Packets of crisps are more air than crisps. A Mars has shrunk but the price has increased, like a Fredo. And they also sell chocolate bars in packets of 4 to add to the illusion of getting more for less.
With bottled water/pop in the UK, most people seem to be fixated on the problem with bottle caps and not noticing the size of the bottles getting smaller.