Watts used by chargers eg laptop, wall warts etc
If you read "Input 240V 1A" then yes, it's supplying 240 watts (maximum).

More likely, you're reading "Input 240V; Output 5V 1A" (or similar). This means that it's outputting 5 watts and (unless it's a linear regulator, which is unlikely) it's drawing just a little bit more than 5W. Even then, the 1A is the maximum that can be supplied by it. If the load is only drawing 1/10 of a watt, the power being supplied is 1/2 watt and the input draw is a little bit more.